3-(Carboxyethyl)-8-Amino-2-Oxo-1,3-Diaza-Spiro-[4.5]-Decane Derivatives

ABSTRACT

The invention relates to 3-(carboxyethyl)-8-amino-2-oxo-1,3-diazaspiro-[4.5]-decane derivatives, their preparation and their use in medicine, particularly in the treatment of pain.

The invention relates to 3-(carboxyethyl)-8-amino-2-oxo-1,3-diazaspiro-[4.5]-decane derivatives, their preparation and use in medicine, particularly in various neurological disorders, including but not limited to pain, neurodegenerative disorders, neuroinflammatory disorders, neuropsychiatric disorders, substance abuse/dependence.

Opioid receptors are a group of Gi/o protein-coupled receptors which are widely distributed in the human body. The opioid receptors are currently subdivided into four major classes, i.e. the three classical opioid receptors mu-opioid (MOP) receptor, kappa-opioid (KOP) receptor, and delta-opioid (DOP) receptor as well as the opioid receptor-like (ORL-1) receptor, which was more recently discovered based on its high homology with said classical opioid receptors. After identification of the endogenous ligand of the ORL-1 receptor, known as nociceptin/orphanin FQ, a highly basic 17 amino acid peptide isolated from tissue extracts in 1995, the ORL-1 receptor was renamed “nociceptin opioid peptide receptor” and abbreviated as “NOP-receptor”.

The classical opioid, receptors (MOP, KOP and DOP) as well as the NOP receptor are widely distributed/expressed in the human body, including in the brain, the spinal cord, on peripheral sensory neurons and the intestinal tract, wherein the distribution pattern differs between the different receptor classes.

Nociceptin acts at the molecular and cellular level in \WV much the same way as opioids. However, its pharmacological effects sometimes differ from, and even oppose those of opioids. NOP-receptor activation translates into a complex pharmacology of pain modulation, which, depending on route of administration, pain model and species involved, leads to either pronociceptive or aminociceptive activity. Furthermore, the NOP receptor system is upregulated under conditions of chronic pain. Systemic administration of selective NOP receptor agonists was found to exert a potent and efficacious analgesia in non-human primate models of acute and inflammatory pain in the absence of side effects. The activation of NOP receptors has been demonstrated, to be devoid of reinforcing effects but to inhibit opioid-mediated reward in rodents and non-human primates (Review: Schroeder et al, Br J Pharmacol 2014; 171 (16): 3777-3800, and references therein).

Besides the involvement of the NOP receptor in nociception, results from preclinical experiments suggest that NOP receptor agonists might be useful inter alia in the treatment of neuropsychiatric disorders (Within et al, Pharmacology & Therapeutics, 141 (2014) 283-299; Jenck et al., Proc. Natl. Acad. Sci. USA 94, 1997, 14854-14858). Remarkably, the DOP receptor is also implicated to modulate not only pain but also neuropsychiatric disorders (Mabrouk et al, 2014; Pradhan et al., 2011).

Strong opioids acting at the MOP receptor site are widely used to treat moderate to severe acute and chronic pain. However, the therapeutic window of strong opioids is limited by severe side effects such as nausea and vomiting, constipation, dizziness, somnolence, respiratory depression, physical dependence and abuse. Furthermore, it is known that MOP receptor agonists show only reduced effectiveness under conditions of chronic and neuropathic pain.

It is known that some of the above mentioned side-effects of strong opioids are mediated by activation of classic opioid-receptors within the central nervous system. Furthermore, peripheral opioid receptors, when activated, can inhibit transmission of nociceptive signals shown in both, clinical and animal studies (Gupta et al., 2001; Kalso et al., 2002; Stein et al., 2003; Zoliner et al., 2008).

Thus, to avoid CNS-mediated adverse effects alter systemic administration, one approach has been to provide peripherally restricted opioid receptor ligands that do not easily cross the blood-brain barrier and therefore distribute poorly to the central nervous system (see for instance WO 2015/192039). Such peripherally acting compounds might combine effective analgesia with limited side-effects.

Another approach has been to provide compounds which interact with both the NOP receptor and the MOP receptor. Such compounds have for instance been described in WO 2004/043967, WO 2012/013343 and WO 2009/118168.

A further approach has been to provide multi-opioid receptor analgesics that modulate more than one of the opioid receptor subtypes to provide additive or synergistic analgesia and/or reduced side effects like abuse liability or tolerance.

On the one hand, it would be desirable to provide analgesics that selectively act on the NOP receptor system but less pronounced on the classic opioid receptor system, especially MOP receptor system, whereas it would be desirable to distinguish between central nervous activity and peripheral nervous activity. On the other hand, it would be desirable to provide analgesics that act on the NOP receptor system and also to a balanced degree on the MOP receptor system, whereas it would be desirable to distinguish between central nervous activity and peripheral nervous activity.

There is a need for medicaments which are effective in the treatment of pain and which have advantages compared to the compounds of the prior art. Where possible, such medicaments should contain such a small dose of active ingredient that satisfactory pain therapy can be ensured without the occurrence of intolerable treatment-emergent adverse events.

It is an object of the invention to provide pharmacologically active compounds, preferably analgesics that have advantages compared to the prior art.

This object has been achieved by the subject-matter of the patent claims.

A first aspect of the invention relates to 3-(carboxyethyl)-8-amino-2-oxo-1,3-diazaspiro-[4.5]-decane derivatives according to general formula (I)

wherein R¹ and R² independently of one another mean —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —OH, —OCH₃, —CN and —CO₂CH₃; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —OH, —OCH₃, —CN and —CO₂CH₃; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted; or a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —OH, —OCH₃, —CN and —CO₂CH₃; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted; or R¹ and R² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆-; —(CH₂)₂—O—(CH₂)₂—; or —(CH₂)₂—NR^(A)—(CH₂)₂—, wherein R^(A) means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —Cl, —Br and —I; preferably with the proviso that R¹ and R² do not simultaneously mean —H; R³ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; R⁴ means

—H;

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said —C₁-C₆-alkyl is optionally connected through —C(═O)—, —C(═O)O—, or —S(═O)₂—; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(—O)O—CH₂—, or —S(═O)₂—; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 6-14-membered aryl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 5-14-membered heteroaryl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; X means —O—, —S— or —NR⁶—; R⁵ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-lumbered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; in case X means NR⁶, R⁶ means

—H;

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a 3-12-membered heterocycloalkyl moiety; saturated or unsaturated, unsubstituted, mono- or polysubstituted; R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ independently of one another mean —H, —F, —Cl, —Br, —I, —OH, or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or R⁷ and R⁸ together with the carbon atom to which they are attached form a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein “mono- or polysubstituted” means that one or more hydrogen atoms are replaced by a substituent independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —R²¹, —C(═O)R²¹, —C(═O)OR²¹, —C(═O)NR²¹R²², —O—(CH₂CH₂—O)₁₋₃₀—H, —O—(CH₂CH₂—O)₁₋₃₀—CH₃, ═O, —OR²¹, —OC(═O)R²¹, —OC(═O)OR²¹, —OC(═O)NR²¹R²², —NO₂, —NR²¹R²², —NR²¹—(CH₂)₁₋₆—C(═O)R²², —NR²¹—(CH₂)₁₋₆—C(═O)OR²², —NR²³—(CH₂)₁₋₆—C(═O)NR²¹R²², —NR²¹C(═O)R²², —NR²¹C(═O)—OR²², —NR²³C(═O)NR²¹R²², —NR²¹S(═O)₂R²², —SR²¹, —S(═O)R²¹, —S(═O)₂R²¹, —S(═O)₂OR²¹, and —S(═O)₂NR²¹R²², wherein R²¹, R²² and R²³ independently of one another mean

—H

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, and —O—C₁-C₆-alkyl; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated; unsubstituted, wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched; saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl, or R²¹ and R²² within —C(═O)NR²¹R²², —OC(═O)NR²¹R²², —NR²¹R²², —NR²³—(CH₂)₁₋₆—C(═O)NR²¹R²², —NR²³C(═O)NR²¹R²², or —S(═O)₂NR²¹R²² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆-; —(CH₂)₂—O—(CH₂)₂—; or —(CH₂)₂—NR^(B)—(CH₂)₂—, wherein R^(B) means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F; —Cl, —Br and —I; or a physiologically acceptable salt thereof.

Preferably, aryl includes but is not limited to phenyl and naphthyl. Preferably, heteroaryl includes but is not limited to -1,2-benzodioxole, -pyrazinyl, -pyridazinyl, -pyridinyl, -pyrimidinyl, -thienyl, -imidazolyl, -benzimidazolyl, thiazolyl, -1,3,4-thiadiazolyl, -benzothiazolyl, -oxazolyl, -benzoxazolyl, -pyrazolyl, -quinolinyl, -isoquinolinyl, -quinazolinyl, -indolyl, -indolinyl, -benzo[c][1,2,5]oxadiazolyl, -imidazo[1,2-a]pyrazinyl, or -1H-pyrrolo[2,3-b]pyridinyl. Preferably, cycloalkyl includes hut is not limited to -cyclopropyl, -cyclobutyl, -cyclopentyl and -cyclohexyl. Preferably, heterocycloalkyl includes but is not limited to -aziridinyl, -azetidinyl, -pyrrolidinyl, -piperidinyl, -piperazinyl, -morpholinyl, -sulfamorpholinyl, oxiridinyl, -oxetanyl, -tetrahydropyranyl, and -pyranyl.

When a moiety is connected through an asymmetric group such as —C(═O)O— or —C(═O)O—CH₂—, said asymmetric group may be arranged in either direction. For example, when R⁴ is connected to the core structure through. —C(═O)O—, the arrangement may be either R⁴—C(═O)O-core or core-C(═O)O—R⁴.

In preferred embodiments of the compound according to the invention,

R⁷ and R⁸ independently of one another mean —H or —C₁-C₆-alkyl; preferably —H or —CH₃; or R⁷ and R⁸ together with the carbon atom to which they are attached form a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; preferably cyclopropyl, cyclobutyl or cyclopentyl, in each case unsubstituted; or a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; preferably oxetanly, tetrahydrofuranyl or tetrahydropyranyl, in each case unsubstituted; and/or R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ independently of one another mean —H, —F, or —C₁-C₆-alkyl; preferably —H.

In a preferred embodiment of the compound according to the invention, R¹ means —H, and R² means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R¹ means —H and R² means —CH₃.

In another preferred embodiment of the compound according to the invention, R¹ means —CH₃; and R² means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R¹ means —CH₃ and R² means —CH₃.

In still another preferred embodiment of the compound according to the invention, R¹ and R² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆—. Preferably, R¹ and R² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃—.

In yet another preferred embodiment,

-   -   R¹ means or —CH₃, and     -   R² means a 3-12-membered cycloalkyl moiety, saturated or         unsaturated, unsubstituted; wherein said 3-12-membered         cycloalkyl moiety is connected through —CH₂—, unsubstituted;         preferably —CH₂-cycloalkyl, —CH₂-cyclobutyl or —CH₂-cyclopentyl;         or R² means a 3-12-membered heterocycloalkyl moiety, saturated         or unsaturated, unsubstituted; wherein said 3-12-membered         heterocycloalkyl moiety is connected through —CH₂-unsubstituted;         preferably —CH₂-oxetanyl or —CH₂-tetrahydrofuranyl.

In a preferred embodiment of the compound according to the invention, R³ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R³ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or monosubstituted with —OCH₃.

In another preferred embodiment of the compound according to the invention, R³ means a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted, optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted. In a preferred embodiment, R³ means -phenyl unsubstituted, mono- or polysubstituted. More preferably, R³ means -phenyl unsubstituted, mono- or disubstituted with —F, —Cl, —CH₃, —CF₃, —OH, —OCH₃, —OCF₃ or —OCH₂OCH₃, preferably —F. In another preferred embodiment, R³ means -benzyl unsubstituted, mono- or polysubstituted. More preferably, R³ means -benzyl unsubstituted, mono- or disubstituted with —F, —Cl, —CF₃, —OH, —OCF₃, —OCF₃ or —OCH₂OCH₃, preferably —F.

In still another preferred embodiment of the compound according to the invention, R³ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted. Preferably, R³ means -thienyl or -pyridinyl, in each case unsubstituted, mono- or polysubstituted. More preferably, R³ means -thienyl, -pyridinyl, -imidazolyl or benzimidazolyl, in each case unsubstituted or monosubstituted with —F, —CI or —CH₃.

In a preferred embodiment of the compound according to the invention, R⁴ means —H.

In another preferred embodiment of the compound according to the invention, R⁴ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁴ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or monosubstituted with a substituent selected from the group consisting of —F, —Cl, —Br, —I, —CN, —CF₃, —OH, —O—C₁-C₄-alkyl, —OCF₃, —O—(CH₂CH₂—O)₁₋₃₀—H, —O—(CH₂CH₂—O)₁₋₃₀—CH₃, —OC(═O)C₁-C₄-alkyl, —C(═O)C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl; —C(═O)NHC₁-C₄-alkylene-CN, —C(═O)NHC₁-C₄-alkylene-O—C₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl, and —S(═O)₂C₁-C₄-alkyl; or with —C(═O)NR²¹R²² wherein R²¹ and R²² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆—, —(CH₂)₂—O—(CH₂)₂—, or —(CH₂)₂—NR^(B)—(CH₂)₂—, wherein R^(B) means —H or —C₁-C₆-alkyl; or with —C(═O)NH-3-12-membered cycloalkyl, saturated or unsaturated, unsubstituted or monosubstituted with —F, —Cl, —Br, —I, —CN, or —OH; or with —C(═O)NH-3-12-membered heterocycloalkyl, saturated or unsaturated, unsubstituted or monosubstituted with —F, —Cl, —Br, —I, —CN, or —OH; More preferably, R⁴ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or monosubstituted with —O—C₁-C₄-alkyl or —O(═O)N(C₁-C₄-alkyl)₂.

In still another preferred embodiment of the compound according to the invention, R⁴ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein the 3-12-membered cycloalkyl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁴ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is connected through —CH₂— or —CH₂CH₂—. More preferably, R⁴ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄ alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl, wherein said 3-12-membered cycloalkyl moiety is connected through —CH₂— or —CH₂CH₂—.

In a preferred embodiment of the compound according to the invention. R⁴ means a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁴ means a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is connected through —CH₂— or —CH₂CH₂—. More preferably, R⁴ means -oxetanyl, -tetrahydrofuranyl or -tetrahydropyranyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl; wherein said -oxetanyl, -tetrahydrofuranyl or -tetrahydropyranyl is connected through —CH₂— or —CH₂CH₂—.

In yet another preferred embodiment of the compound according to the invention, R⁴ means a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is connected through. —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁴ means -phenyl, unsubstituted, mono- or polysubstituted; wherein said -phenyl is connected through —CH₂— or —CH₂CH₂—. More preferably, R⁴ means -phenyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl, wherein said -phenyl is connected through —CH₂— or —CH₂CH₂—.

In a further preferred embodiment of the compound, according to the invention, R⁴ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁴ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said -phenyl is connected through —CH₂— or —CH₂CH₂—. More preferably, R⁴ means -pyridinyl, -pyrimidinyl, -pyrazinyl, or -pyrazolinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl; wherein said -pyridinyl, -pyrimidinyl, -pyrazinyl, or -pyrazolinyl is connected through —CH₂— or —CH₂CH₂—.

In a preferred embodiment of the compound according to the invention, R⁵ means —H.

In another preferred embodiment of the compound according to the invention, R⁵ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁵ means —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted, mono- or polysubstituted. More preferably, R⁵ means —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted or monosubstituted with a substituent selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl.

In still another preferred embodiment of the compound according to the invention, R⁵ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted, wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; preferably through —CH₂— or —CH₂CH₂—. Preferably, R⁵ means a 3-6-membered cycloalkyl moiety, saturated, unsubstituted, mono- or polysubstituted, wherein said 3-12-membered cycloalkyl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated, unsubstituted. More preferably, R⁵ means -cyclobutyl, unsubstituted or monosubstituted with —F, —OH, —CN or —C₁-C₄-alkyl, wherein said -cyclobutyl is connected through —CH₂— or —CH₂CH₂—.

In yet another preferred embodiment of the compound according to the invention, R⁵ means a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁵ means a 4-6-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted. More preferably, R⁵ means -heterocyclobutyl, unsubstituted.

In a further preferred embodiment of the compound according to the invention, R⁵ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁵ means a 5-6-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted, Wherein said 5-6-membered heteroaryl moiety is optionally connected through —CH₂—. More preferably, R⁵ means a 5-6-membered heteroaryl moiety, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl, wherein said 5-6-membered heteroaryl moiety is optionally connected through —CH₂—. Still more preferably, R⁵ means -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —C₁-C₄-alkyl, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, S(═O)C₁-C₄-alkyl and —S(═O)₂C₁-C₄-alkyl, wherein said -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl is optionally connected through —CH₂—.

In a preferred embodiment of the compound according to the invention, X means NR⁶ and R⁵ and R⁶ together with the nitrogen atom to which they are attached form a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, X means NR⁶ and R⁵ and R⁶ together with the nitrogen atom to which they are attached form a 5-6-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted. More preferably, X means NR⁶ and R⁵ and R⁶ together with the nitrogen atom to which they are attached form -pyrrolidinyl, -morpholinyl, -thiomorpholinyl, -thiomorpholinyl dioxide, or -piperazinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of ═O, —OH, and —C(═O)NH₂, wherein said -pyrrolidinyl, -pyrimidinyl, -morpholinyl, -thiomorpholinyl, -thiomorpholinyl dioxide, or -piperazinyl is optionally condensed with an imidazole moiety, unsubstituted.

In a preferred embodiment of the compound according to the invention, R⁵ means

—H;

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —OH, —S(═O)C₁-C₄-alkyl and —S(═O)₂ C₁-C₄-alkyl; -cyclobutyl, unsubstituted or monosubstituted with —OH; wherein said -cyclobutyl is connected through —CH₂—; -heterocyclobutyl, unsubstituted; or -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, Br, —I, —OH, —O—C₁-C₄-alkyl, —CN, and —S(═O)₂C₁-C₄-alkyl; wherein said -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl is optionally connected through —CH₂—; in case X means NR⁶, R⁶ means —H or —CH₃; or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a piperidine moiety, a pyrrolidine moiety, a morpholine moiety, a thiomorpholine moiety, a thiomorpholine dioxide moiety, or a piperazine moiety, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of ═O, —OH, and —C(═O)NH₂; wherein said piperidine moiety, pyrrolidine moiety, morpholine moiety, thiomorpholine moiety, thiomorpholine dioxide moiety, or piperazine moiety is optionally condensed with an imidazole moiety, unsubstituted.

In a preferred embodiment of the compound according to the invention, X means NR⁶ and R⁶ means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted. Preferably, R⁶ means —H or —CH₃. More preferably, R⁶ means —H.

In preferred embodiments the compound according to the invention has a structure according to any of general formulas (II-A) to (VIII-C):

wherein in each case R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, and X are defined as above, R^(C) means —H, —OH, —F, —CN or —C₁-C₄-alkyl; preferably —H or —OH; R^(D) means —H or —F; or a physiologically acceptable salt thereof

Preferably, the substructure of the compounds according to general formula (I) represented by —C(═O)—X—R⁵ (R⁵, X, R⁷, R⁸, R⁹ and R¹⁰), i.e.

or the corresponding substructure of any of above general formulas (II-A) to (VIII-C) has preferably a meaning selected from the grout) consisting of:

In particularly preferred embodiments of the compound according to the invention,

R¹ means —H or —CH₃; and/or R² means —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted; preferably. R² means —CH₃ or —CH₂CH₃; more preferably, R¹ and R² both mean —CH₃; and/or R³ means -phenyl, -thienyl or -pyridinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —CN, —CH₃, —CH₂CH₃, —CH₂F, —CHF₂, —CF₃, —OCF3, —OH; —OCH₃, —C(═O)NH₂, C(═O)NHCH₃, —C(═O)N(CH₃)₂, —NH₂, —NHCH₃, —N(CH₃)₂, —NHC(═O)CH₃, —CH₂OH, —SOCH₃ and —SO₂CH₃; preferably, R³ imam -phenyl, -thienyl or -pyridinyl, in each case unsubstituted or substituted with —F; more preferably, R³ means phenyl, unsubstituted or monosubstituted with —F; and/or R⁴ means

—H;

—C₁-C₆-alkyl; linear or branched, saturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl; 3-6-membered cycloalkyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered cycloalkyl is connected through —C₁-C₆-alkylene; preferably, R⁴ means 3-6-membered cycloalkyl, unsubstituted or substituted with one; two, three or four substituents independently of one another selected from the group consisting of —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered cycloalkyl is connected through —CH₂— or —CH₂CH₂—; more preferably, R⁴ means -cyclopropyl or -cyclobutyl, unsubstituted or monosubstituted with —OH, wherein said -cyclopropyl or -cyclobutyl is connected through —CH₂—; or 3-6-membered heterocycloalkyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered heterocycloalkyl is connected through —C₁-C₆-alkylene; and/or X means —O— or —NR⁶—; and/or R⁵ means

—H;

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —OH, —S(═O)C₁-C₄-alkyl and —S(═O)₂ C₁-C₄-alkyl; -cyclobutyl, unsubstituted or monosubstituted with —OH; wherein said -cyclobutyl is connected through —CH₂—; -heterocyclobutyl, unsubstituted; or -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —II, —Cl, Br, —I, —OH, —O—C₁-C₄-alkyl, and —S(═O)₂C₁-C₄-alkyl; wherein said -oxazolyl, -pyridazinyl or -pyrimidinyl is optionally connected through —CH₂—; preferably pyridinyl or pyridazinyl, in each case unsubstituted; and/or in case X means NR⁶, R⁶ means —H or —CH₃, preferably —H; or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a piperidine moiety, a pyrrolidine moiety, a morpholine moiety, a thiomorpholine moiety, a thiomorpholine dioxide moiety, or a piperazine moiety, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of ═O, —OH, and —C(═O)NH₂; wherein said piperidine moiety, pyrrolidine moiety, morpholine moiety, thiomorpholine moiety, thiomorpholine dioxide moiety, or piperazine moiety is optionally condensed with an imidazole moiety, unsubstituted; and/or R⁷ and R⁸ independently of one another mean —H or —CH₃; or R⁷ and R⁸ together with the carbon atom to which they are attached form a ring selected from the group consisting of cyclopropyl, cyclobutyl, heterocyclobutyl and heterocyclohexyl, in each case unsubstituted; and/or R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ mean —H.

In particularly preferred embodiments of the compound according to the invention,

R¹ means —H or —CH₃; and/or R² means —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted; preferably, R² means —CH₃ or —CH₂CH₃; more preferably, R¹ and R² both mean —CH₃; and/or R³ means -phenyl, -thienyl or -pyridinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —CN, —CH₃, —CH₂CH₃, —CH₂F, —CHF₂, —CF₃, —OCF3, —OH, —OCH₃, —C(═O)NH₂, C(═O)NHCH₃, —C(═O)N(CH₃)₂, —NH₂, —NHCH₃, —N(CH₃)₂, —NHC(═O)CH₃, —CH₂OH, SOCH₃ and SO₂CH₃; preferably, R³ means -phenyl, -thienyl or -pyridinyl, in each case unsubstituted or substituted with —F; more preferably, R³ means phenyl, unsubstituted; and/or R⁴ means

—H:

—C₁-C₆-alkyl, linear or branched, saturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl; or 3-6-membered cycloakyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered cycloalkyl is connected through —C₁-C₆-alkylene; preferably, R⁴ means 3-6-membered cycloalkyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered cycloalkyl is connected through —CH₂— or —CH₂CH₂—, more preferably, R⁴ means -cyclobutyl, unsubstituted or monosubstituted with —OH, wherein said -cyclobutyl is connected through —CH₂—, and/or X means —O— or —NR⁶—; and/or R⁵ means

—H;

—C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂: —OH, —S(═O)C₁-C₄-alkyl and —S(═O)₂ C₁-C₄-alkyl; -cyclobutyl, unsubstituted or monosubstituted with —OH; wherein said -cyclobutyl is connected through —CH₂—; -heterocyclobutyl, unsubstituted; or -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, Br, —I, —OH, —O—C₁-C₄-alkyl, —CN, and —S(═O)₂C₁-C₄-alkyl; wherein said -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl is optionally connected through —CH₂—; preferably pyridinyl or pyridazinyl, in each case unsubstituted; and/or in case X means NR⁶, R⁶ means —H or —CH₃, preferably R⁶ means —H; and/or or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a piperidine moiety, a pyrrolidine moiety, a morpholine moiety, a thiomorpholine moiety, a thiomorpholine dioxide moiety, or a piperazine moiety, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of ═O, —OH, and —C(═O)NH₂; wherein said piperidine moiety, pyrrolidine moiety, morpholine moiety, thiomorpholine moiety, thiomorpholine dioxide moiety, or piperazine moiety is optionally condensed with an imidazole moiety, unsubstituted; and/or R⁷ and R⁸ independently of one another mean —H or —CH₃; and/or R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ mean —H.

Preferably, the compound according to the invention is selected from the group consisting of

SC_5001 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide SC_5002 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-propionamide SC_5003 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(2-methoxy-pyridin-4-yl)-propionamide SC_5004 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(6-methoxy-pyridin-3-yl)-propionamide SC_5005 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(3-methoxy-pyridin-4-yl)-propionamide SC_5006 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(6-methoxy-pyridazin-3-yl)-propionamide SC_5007 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(5-methylsulfonyl-pyridin-2-yl)-propionamide SC_5008 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(5-methoxy-pyridin-2-yl)-propionamide SC_5009 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(6-methylsulfonyl-pyridin-3-yl)-propionamide SC_5010 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(6-methoxy-pyrazin-2-yl)-propionamide SC_5011 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(4-methoxy-pyridin-2-yl)-propionamide SC_5012 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(oxazol-5-yl-methyl)-propionamide SC_5013 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(oxazol-2-yl-methyl)-propionamide SC_5014 CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-piperidin-1-yl]-3-oxo-propyl]-8-dimethylamino- 8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5015 CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo-propyl]-8- dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5016 CIS-1-(Cyclobutyl-methyl)-3-[3-[(3S,4R)-3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo-propyl]-8- dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5017 CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3-[3-(3-hydroxy-piperidin-1-yl)-3-oxo-propyl]-8- phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5018 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-[(1-hydroxy-cyclobutyl)-methyl]-propionamide SC_5019 CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3-[3-oxo-3-(5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5- a]pyrazin-7-yl)-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5020 CIS-3-[3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3- yl]-propanoylamino]-N,N-dimethyl-propionamide SC_5022 CIS-N-(2-Cyano-pyrimidin-5-yl)-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo- 8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide SC_5023 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyrimidin-2-yl-propionamide SC_5024 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(4-hydroxy-pyrimidin-2-yl)-propionamide SC_5025 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(4-methoxy-pyrimidin-2-yl)-propionamide SC_5026 CIS-3-[1-(Cyclobutyl-methyl)-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- 2,2-dimethyl-propionamide SC_5027 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide SC_5028 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-propionamide SC_5029 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5030 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide SC_5031 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N- (2-hydroxy-ethyl)-propionamide SC_5032 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N- methyl-propionamide SC_5033 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N- pyrimidin-5-yl-propionamide SC_5034 CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- 2,2-dimethyl-propionamide SC_5035 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- 2,2-dimethyl-propionamide SC_5036 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyridin-3-yl-propionamide SC_5037 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyridin-4-yl-propionamide SC_5038 CIS-2-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3- yl]-propanoylamino]-2-methyl-propionamide SC_5039 CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(2-methylsulfonyl-ethyl)-propionamide SC_5040 CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- N-(2-hydroxy-ethyl)-propionamide SC_5041 CIS-8-Dimethylamino-1-(3-methoxy-propyl)-3-[3-oxo-3-(3-oxo-piperazin-1-yl)-propyl]-8- phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5042 CIS-(2R)-1-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-propanoyl]-pyrrolidine-2-carboxylic acid amide SC_5043 CIS-N-(Carbamoyl-methyl)-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-propionamide SC_5044 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyridin-2-yl-propionamide SC_5045 CIS-3-[1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan- 3-yl]-2,2-dimethyl-propionamide SC_5046 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- 2,2-dimethyl-propionamide SC_5047 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- propionamide SC_5048 CIS-3-[1-(Cyclobutyl-methyl)-8-[methyl-(2-methyl-propyl)-amino]-2-oxo-8-plenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5049 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N- methyl-propionamide SC_5051 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-pyrimidin-5-yl-propionamide SC_5052 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5053 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-ethyl)-propionamide SC_5054 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide SC_5055 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide SC_5056 CIS-N-(Carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-dimethyl-amino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5057 CIS-N-(Carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5058 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phethyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5059 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide SC_5060 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5064 CIS-3-[8-(Ethyl-methyl-amino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl- propionamide SC_5066 CIS-3-[8-(Ethyl-methyl-amino)-1-methyl-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2- dimethyl-propionamide SC_5067 CIS-2,2-Dimethyl-3-(8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)- propionamide SC_5069 CIS-3-(8-Ethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl-propionamide SC_5070 CIS-3-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl-propionamide SC_5071 CIS-3-[1-(Cyclobutyl-methyl)-8-ethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2- dimethyl-propionamide SC_5072 CIS-3-[8-Dimethylamino-1-(oxetan-3-yl-methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]- 2,2-dimethyl-propionamide SC_5073 CIS-3[1-(Cyclopropyl-methy])-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3- yl]-2,2-dimethyl-propionamide SC_5074 CIS-3-[8-(Ethyl-methyl-amino)-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5076 CIS-8-Dimethylamino-3-(2,2-dimethyl-3-morpholin-4-yl-3-oxo-propyl)-1-[(1-hydroxy- cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5077 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-y]-N-(2-hydroxy-ethyl)-2,2-dimethyl-propionamide SC_5078 CIS-3-[1-[(1-Cyano-cyclobutyl)-methy]-8-dimethylamino-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5079 CIS-8-Dimethylamino-3-[3-(1,1-dioxo-[1,4]thiazinan-4-yl)-2,2-dimethyl-3-oxo-propyl]-1-[(1- hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5081 TRANS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5082 TRANS-3-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl- propionamide SC_5083 CIS-3-[1-(Cyclopropyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-2-oxo-1,3- diazaspiro[4.5]decan-3-yl]-N,N-dimethyl-propionamide SC_5084 CIS-3-[1-(Cyclopropyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-2-oxo-1,3- diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5085 CIS-1-((1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3- yl)methyl)cyclopropanecarboxamide SC_5086 CIS-3-((1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3 - yl)methyl)oxetane-3-carboxamide SC_5087 CIS-3-(1-(cyclopropylmethyl)-8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)- 2,2-dimethylpropanamide SC_5088 CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3- yl)propanamide SC_5089 CIS-3-(8-(dimethylamino)-1-((1-fluorocyclopropyl)methyl)-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide and the physiologically acceptable salts thereof.

According to the invention, unless expressly stated otherwise, “—C₁-C₄-alkyl”, “—C₁-C₆-alkyl” and any other alkyl residues can be linear or branched, saturated or unsaturated. Linear saturated alkyl includes methyl, ethyl, n-propyl, n-butyl, n-pentyl and n-hexyl. Examples of branched saturated, alkyl include but are not limited to iso-propyl, sec-butyl, and tert-butyl. Examples of linear unsaturated alkyl include but are not limited to vinyl, propenyl, allyl, and propargyl.

According to the invention, unless expressly stated otherwise, “—C₁-C₄-alkyl”, “—C₁-C₆-alkyl” and any other alkyl residues can be unsubstituted, mono- or polysubstituted. Examples of substituted alkyl include but are not limited, to —CH₂CH₂OH, —CH₂CH₂OCH₃, —CH₂CH₂CH₂OCH₃, —CH₂CH₂S(═O)₂CH₃, —CH₂C(═O)NH₂, —C(CH₃)₂C(═O)NH₂, —CH₂C(CH₃)₂C(═O)NH₂, and —CH₂CH₂C(═O)N(CH₃)₂.

According to the invention, unless expressly stated otherwise, “—C₁-C₆-alkylene-”, “—C₁-C₄-alkylene” and any other alkylene residue can be unsubstituted, mono- or polysubstituted. Examples of saturated alkylene include but are not limited to —CH₂—, —CH(CH₃)—, —C(CH₃)₂—, —CH₂CH₂—, —CH(CH₃)CH₂—, —CH₂CH(CH₃)—, —CH(CH₃)—CH(CH₃)—, —C(CH₃)₂CH₂—, —CH₂C(CH₃)₂—, —CH(CH₃)C(CH₃)₂—, —C(CH₃)₂CH(CH₃)—, C(CH₃)₂C(CH₃)₂—, —CH₂CH₂CH₂—, and —C(CH₃)₂CH₂CH₂—. Examples of unsaturated alkylene include but are not limited to —CH═CH—, —C≡C—, —C(CH₃)═CH—, —CH═C(CH₃)—, —C(CH₃)═C(CH₃)—, CH₂CH═CH—, —CH═CHCH₂—, —CH═CH—CH═CH—, and —CH═CH—C≡C—.

According to the invention, unless expressly stated otherwise, “—C₁-C₆-alkylene-”, “—C₁-C₄-alkylene” and any other alkylene residue can be unsubstituted, mono- or polysubstituted. Examples of substituted —C₁-C₆-alkylene- include but are not limited to —CHF—, —CF₂—, —CHOH— and —C(═O)—.

According to the invention, moieties may be connected through —C₁-C₆-alkylene-, i.e. the moieties may not be directly bound to the core structure of compound according to general formula (I), but nay be connected to the core structure of compound according to general formula (I) or its periphery through a —C₁-C₆-alkylene-linker.

According; to the invention, “3-12-membered cycloalkyl moiety” means a non-aromatic, monocyclic, bicyclic or tricyclic moiety comprising 3 to 12 ring carbon atoms but no heteroatoms in the ring. Examples of preferred saturated 3-12-membered cycloalkyl moieties according to the invention include but are not limited to cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, hydrindane, and decaline. Examples of preferred unsaturated 3-12-membered cycloalkyl moiety moieties according to the invention include but are not limited to cyclopropene, cyclobutene, cyclopentane, cyclopentadiene, cyclohexene, 1,3-cyclohexadiene, and 1,4-cyclohexadiene. The 3-12-membered cycloalkyl moiety, which is bonded to the compound according to the invention, in its periphery may optionally be condensed with a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; and/or with a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted. Under these circumstances, the ring atoms of the condensed moieties are not included in the 3 to 12 ring atoms of the 3-12-membered cycloalkyl moiety. Examples of 3-12-membered cycloalkyl moieties condensed with 3-12-membered heterocycloalkyl moieties include but are not limited to octahydro-1H-indol, decahydroquinoline, decahydrolsoquinoline, octahydro-2H-benzo[b][1,4]oxazin, and decahydroquinoxalin, which in each case are connected through the 3-12-membered cycloalkyl moiety. Examples of 3-12-membered cycloalkyl moieties condensed with 6-14-membered aryl moieties include but are not limited to 2,3-dihydro-1H-indene and tetraline, which in each case are connected through the 3-12-membered cycloalkyl moiety. Examples of 3-12-membered cycloalkyl moieties condensed with 5-14-membered heteroaryl moieties include but are not limited to 5,6,7,8-tetrahydroquinoline and 5,6,7,8-tetrahydroquinazoline, which in each case are connected through the 3-12-membered cycloalkyl moiety.

According to the invention, the 3-12-membered cycloalkyl moiety may optionally be connected through —C₁-C₆-alkylene-, i.e. the 3-12-membered cycloalkyl moiety may not be directly bound to the compound according to general formula (t) but may be connected thereto through a —C₁-C₆-alkylene-linker, Examples include but are not limited to —CH₂-cyclopropyl, —CH₂-cyclobutyl, —CH₂-cyclopentyl, —CH₂-cyclohexyl, —CH₂CH₂-cyclopropyl, —CH₂CH₂-cyclobutyl, —CH₂CH₂-cyclopentyl, and —CH₂CH₂-cyclohexyl.

According to the invention, unless expressly stated otherwise, the 3-12-membered cycloalkyl moiety can be unsubstituted, mono- or polysubstituted. Examples of substituted 3-12-membered cycloalkyl moieties include but are not limited to —CH₂-1-hydroxy-cyclobutyl.

According to the invention, “3-12-membered heterocycloalkyl moiety” means a non-aromatic, monocyclic, bicyclic or tricyclic moiety comprising 3 to 12 ring atoms, wherein each cycle comprises independently of one another 1, 2, 3, 4 or more heteroatoms independently of one another selected from the group consisting of nitrogen, oxygen and sulfur, whereas sulfur may be oxidized (S(═O) or (S(═O)₂), whereas the remaining ring atoms are carbon atoms, and whereas bicyclic or tricyclic systems may share common heteroatom(s). Examples of preferred saturated 3-12-membered heterocycloalkyl moieties according to the invention include but are not limited to aziridin, azetidine, pyrrolidine, imidazolidine, pyrazolidine, piperidine, piperazine, triazolidine, tetrazolidine, oxiran, oxetane, tetrahydrofurane, tetrahydropyrane, thiirane, thietane, tetrahydrothiophene, diazepane, oxazolidine, isoxazolidine, thiazolidine, isothiazolidine, thiadiazolidine, morpholine, thiomorpholine. Examples of preferred unsaturated 3-12-membered heterocycloalkyl moiety moieties according to the invention include but are not limited to oxazoline, pyrazoline, imidazoline, isoxazoline, thiazoline, isothiazoline, and dihydropyran. The 3-12-membered heterocycloalkyl moiety, which is bonded to the compound according to the invention, in its periphery may optionally be condensed with a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; and/or with a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted. Under these circumstances, the ring atoms of the condensed moieties are not included in the 3 to 12 ring atoms of the 3-12-membered heterocycloalkyl moieties. Examples of 3-12-membered heterocycloalkyl moieties condensed with 3-12-membered cycloalkyl moieties include but are not limited to octahydro-1H-indol, decahydroquinoline, decahydroisoquinoline, octahydro-2H-benzo[b][1,4]-oxazin, and, decahydroquinoxalin, which in each case are connected through the 3-12-membered heterocycloalkyl moiety. An examples of a 3-12-membered heterocycloalkyl moiety condensed with a 6-14-membered aryl moiety includes but is not limited to 1,2,3,4-tetrahydroquinoline, which is connected through the 3-12-membered heterocycloalkyl moiety. An example of a 3-12-membered heterocycloalkyl moiety condensed with a 5-14-membered heteroaryl moieties includes but is not limited to 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine, which is connected through the 3-12-membered heterocycloalkyl moiety.

According to the invention, the 3-12-membered heterocycloalkyl moiety may optionally be connected through —C₁-C₆-alkylene-, i.e. the 3-12-membered heterocycloalkyl moiety may not be directly bound to the compound according to general formula (I) but may be connected thereto through a —C₁-C₆-alkylene-linker. Said linker may be connected to a carbon ring atom or to a hetero ring atom of the 3-12-membered heterocycloalkyl moiety. Examples include but are not limited to —CH₂-oxetane, —CH₂-pyrrolidine, —CH₂-piperidine, —CH₂-morpholine, —CH₂CH₂-oxetane, —CH₂CH₂-pyrrolidine, —CH₂CH₂-piperidine, and —CH₂CH₂-morpholine.

According to the invention, unless expressly stated otherwise, the 3-12-membered heterocycloalkyl moiety can be unsubstituted, mono- or polysubstituted. Examples of substituted 3-12-membered heterocycloalkyl moieties include but are not limited to 2-carboxamido-N-pyrrolidinyl-, 3,4-dihydroxy-N-pyrrolidinyl, 3-hydroxy-N-pyrimidinyl, 3,4-dihydroxy-N-pyrimidinyl, 3-oxo-N-piperazinyl, -tetrahydro-2H-thiopyranyl dioxide and thiomorpholinyl dioxide.

According to the invention, “6-14-membered aryl moiety” means an aromatic, monocyclic, bicyclic or tricyclic moiety comprising 6 to 14 ring carbon atoms but no heteroatoms in the ring. Examples of preferred 6-14-membered aryl moieties according, to the invention include but are not limited to benzene, naphthalene, anthracen, and phenanthren. The 6-14-membered aryl moiety, which is bonded to the compound according to the invention, in its periphery may optionally be condensed with a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted. Under these circumstances, the ring atoms of the condensed moieties are not included in the 6 to 14 ring carbon atoms of the 6-14-membered heterocycloalkyl moieties. Examples of 6-14-membered aryl moieties condensed with 3-12-membered cycloalkyl moieties include but are not limited to 2,3-dihydro-1H-indene and tetraline, which in each case are connected through the 6-14-membered aryl moiety. An example of a 6-14-membered aryl moiety condensed with a 3-12-membered heterocycloalkyl moiety includes but is not limited to 1,2,3,4-tetrahydroquinoline, which is connected through the 6-14-membered aryl moiety. Examples of 6-14-membered aryl moieties condensed with 5-14-membered heteroaryl moieties include but are not limited to quinoline, isoquinoline, phenazine and phenoxacine, which in each case are connected through the 6-14-membered aryl moiety.

According to the invention, the 6-14-membered aryl moiety may optionally be connected through —C₁-C₆-alkylene-, i.e. the 6-14-membered aryl moiety may not be directly bound to the compound according to general formula (I) but may be connected thereto through a —C₁-C₆-alkylene-linker. Said linker may be connected to a carbon ring atom or to a hetero ring atom of the 6-14-membered aryl moiety. Examples include but are not limited to —CH₂—C₆H₅, —CH₂CH₂—C₆H₅ and —CH═CH—C₆H₅.

According to the invention, unless expressly stated otherwise, the 6-14-membered aryl moiety can be unsubstituted, mono- or polysubstituted. Examples of substituted 6-14-membered aryl moieties include but are not limited to 2-fluorophenyl, 3-fluorophenyl, 2-methoxyphenyl and 3-methoxyphenyl.

According to the invention, “5-14-membered heteroaryl moiety” means an aromatic, monocyclic, bicyclic or tricyclic moiety comprising 6 to 14 ring atoms, wherein each cycle comprises independently of one another 1, 2, 3, 4 or more heteroatoms independently of one another selected from the group consisting of nitrogen, oxygen and sulfur, whereas the remaining ring atoms are carbon atoms, and whereas bicyclic or tricyclic systems may share common heteroatom(s). Examples of preferred 5-14-membered heteroaryl moieties according to the invention include but are not limited to pyrrole, pyrazole, imidazole, triazole, tetrazole, furane, thiophene, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyridazine, pyrimidine, pyrazine, indolicine, 9H-chinolicine, 1,8-naphthyridine, purine, imidazo[1,2-a]pyrazine, and pteridine. The 5-14-membered heteroaryl moiety, which is bonded to the compound according to the invention, in its periphery may optionally be condensed with a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; and/or with a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted. Under these circumstances, the ring atoms of the condensed moieties are not included in the 6 to 14 ring carbon atoms of the 6-14-membered heterocycloalkyl moieties. Examples of 5-14-membered heteroaryl moieties condensed with 3-12-membered cycloalkyl moieties include but are not limited to 5,6,7,8-tetrahydroquinoline and 5,6,7,8-tetrahydroquinazoline, which in each case are connected through the 5-14-membered heteroaryl moiety. An examples of a 5-14-membered heteroaryl moiety condensed with a 3-12-membered heterocycloalkyl moiety includes but is not limited to 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine, which is connected through the 5-14-membered heteroaryl moiety. Examples of 5-14-membered heteroaryl moieties condensed with 6-14-membered aryl moieties include but are not limited to quinoline, isoquinoline, phenazine and phenoxacine, which in each case are connected through the 5-14-membered heteroaryl moiety.

According to the invention, the 5-14-membered heteroaryl moiety may optionally be connected through —C₁-C₆-alkylene-, i.e. the 5-14-membered heteroaryl moiety may not be directly bound to the compound according to general formula (I) but may be connected thereto through a —C₁-C₆-alkylene-linker. Said linker may be connected to a carbon ring atom or to a hetero ring atom of the 5-14-membered heteroaryl moiety. Examples include but are not limited to —CH₂-oxazole, —CH₂-isoxazole, —CH₂-imidazole, —CH₂-pyridine, —CH₂-pyrimidine, —CH₂-pyridazine, —CH₂CH₂-oxazole, —CH₂CH₂-isoxazole, —CH₂CH₂-imidazole, —CH₂CH₂-pyridine, —CH₂CH₂-pyrimidine, and —CH₂CH₂-pyridazine.

According to the invention, unless expressly stated otherwise, the 5-14-membered heteroaryl moiety can be unsubstituted, mono- or polysubstituted. Examples of 5-14-membered heteroaryl moieties include but are not limited to 2-methoxy-4-pyridinyl, 2-methoxy-5-pyridinyl, 3-methoxy-4-pyridinyl, 3-methoxy-6-pyridinyl, 4-methoxy-2-pyridinyl, 2-methylsulfonyl-5-pyridinyl, 3-methylsulfonyl-6-pyridinyl, 3-methoxy-6-pyridazinyl, 2-nitrilo-5-pyrimidinyl, 4-hydroxy-2-pyrimidinyl, 4-methoxy-pyrimidinyl, and 2-methoxy-6-pyrazinyl.

Preferably, the compounds according to the invention have a structure according to general formula (I′)

wherein R¹ to R⁵, R⁷ to R²⁰, and X are defined as above, or a physiologically acceptable salt thereof.

In one preferred embodiment, the excess of the cis-isomer so designated is at least 50% de, more preferably at least 75% de, yet more preferably at least 90% de, most preferably at least 95% de and in particular at least 99% de.

In particularly preferred embodiments, the compound according to the invention has a structure according to general formula (IX)

wherein R^(C) means —H or —OH, R^(D) means —H or —F; R⁵ means —H, —CH₃, or —CH₂CH₂—OH; R⁶ means —H or —CH₃; and R⁷ means —CH₃ and R⁸ means —CH₃, or R⁷ and R⁸ together with the carbon atom to which they are attached form a cyclopropyl ring.

When within the moiety corresponding to residue R⁴ the index is 1, the ring is a cyclopropyl ring. When within the moiety corresponding to residue R⁴ the index is 2, the ring is a cyclobutyl ring.

In a preferred embodiment, the compounds according to the invention are in the form of the free bases.

In another preferred embodiment, the compounds according to the invention are in the form of the physiologically acceptable salts.

For the purposes of the description, a “salt” is to be understood as being any form of the compound in which it assumes an ionic form or is charged and is coupled with a counter-ion (a cation or anion) or is in solution. The term is also to be understood as meaning complexes of the compound with other molecules and ions, in particular complexes which are associated via ionic interactions. Preferred salts are physiologically acceptable, in particular physiologically acceptable salts with anions or acids or also a salt formed with a physiologically acceptable acid.

Physiologically acceptable salts with anions or acids are salts of the particular compound in question with inorganic or organic acids which are physiologically acceptable, in particular when used in humans and/or mammals. Examples of physiologically acceptable salts of particular acids include but are not limited to salts of hydrochloric acid, sulfuric acid, and acetic acid.

The invention also includes isotopic isomers of a compound according to the invention, wherein at least one atom of the compound is replaced by an isotope of the respective atom which is different from the naturally predominantly occurring isotope, as well as any mixtures of isotopic isomers of such a compound. Preferred isotopes are ²H (deuterium), ³H (tritium), ¹³C and ¹⁴C.

Certain compounds according to the invention are useful for modulating a pharmacodynamic response from one or more opioid receptors (mu, delta, kappa, NOP/ORL-1) either centrally or peripherally, or both. The pharmacodynamic response may be attributed to the compound either stimulating (agonizing) or inhibiting (antagonizing) the one or more receptors. Certain compounds according to the invention may antagonize one opioid receptor, while also agonizing one or more other receptors. Compounds according to the invention having agonist activity may be either full agonists or partial agonists.

As used herein, compounds that bind to receptors and mimic the regulatory effects of endogenous ligands are defined as “agonists”. Compounds that bind to a receptor hut produce no regulatory effect, but rather block the binding of ligands to the receptor, are defined as “antagonists”.

In certain embodiments, the compounds according to the invention are agonists at the mu opioid (MOP) and/or kappa opioid (KOP) and/or delta opioid (DOP) and/or nociceptin opioid (NOP/ORL-1) receptors.

The compounds according to the invention potently bind to the MOP and/or KOP and/or DOP and/or NOP receptors.

The compounds according to the invention can be modulators at the MOP and/or KOP and/or DOP and/or NOP receptors, mid therefore the compounds according to the invention can be used/administered to treat, ameliorate, or prevent pain.

In some embodiments, the compounds according to the invention are agonists of one or more opioid receptors. In some embodiments, the compounds according to the invention are, agonists of the MOP and/or KOP and/or DOP and/or NOP receptors.

In some embodiments, the compounds according to the invention are antagonists of one or more opioid receptors. In some embodiments, the compounds according to the invention are antagonists of the MOP and/or KOP and/or DOP and/or NOP receptors.

In some embodiments, the compounds according to the invention have both, (i) agonist activity at the NOP receptor; and (ii) agonist activity at one or more of the MOP, KOP, and DOP receptors.

In some embodiments, the compounds according to the invention have both, (i) agonist activity at the NOP receptor; and (ii) antagonist activity at one or more of the MOP, KOP, and DOP receptors.

In some embodiments, the compounds according to the invention have both, antagonist activity at the NOP receptor; and (ii) agonist activity at one or more of the MOP, KOP, and DOP receptors.

In some embodiments, the compounds according to the invention have both, (i) antagonist activity at the NOP receptor; and (ii) antagonist activity at one or more of the MOP, KOP, and DOP receptors.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have selective agonist activity at the NOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention

-   -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the KOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the DOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the N. OP receptor as well as no significant         activity at the DOP receptor; or     -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor as well as no significant activity at the         DOP receptor.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have balanced agonist activity at the NOP receptor as well as at the MOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention

-   -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor as well as agonist activity at the         KOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor as well as agonist activity at the         DOP receptor;     -   can be regarded as opioid pan agonists, i.e. have agonist         activity at the NOP receptor as well as agonist activity at the         MOP receptor as well as agonist activity at the KOP receptor as         well as agonist activity at the DOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor, but no significant activity at the         KOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor, but no significant activity at the         DOP receptor; or     -   have agonist activity at the NOP receptor as well as agonist         activity at the MOP receptor, but no significant activity at the         KOP receptor as well as no significant activity at the DOP         receptor.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have balanced agonist activity at the NOP receptor as well as at the KOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention

-   -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor as well as agonist activity at the         MOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor as well as agonist activity at the         DOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor, but no significant activity at the         MOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor, but no significant activity at the         DOP receptor; or     -   have agonist activity at the NOP receptor as well as agonist         activity at the KOP receptor, but no significant activity at the         MOP receptor as well as no significant activity at the DOP         receptor.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have balanced agonist activity at the NOP receptor as well as at the DOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention

-   -   have agonist activity at the NOP receptor as well as agonist         activity at the DOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         MOP receptor;     -   have agonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         KOP receptor; or     -   have agonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         MOP receptor as well as no significant activity at the KOP         receptor.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have selective agonist activity at the KOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention

-   -   have agonist activity at the KOP receptor, but no significant         activity at the MOP receptor;     -   have agonist activity at the KOP receptor, but no significant         activity at the NOP receptor;     -   have agonist activity at the KOP receptor, but no significant         activity at the DOP receptor;     -   have agonist activity at the KOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the NOP receptor;     -   have agonist activity at the KOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the DOP receptor; or     -   have agonist activity at the KOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the NOP receptor as well as no significant activity at the         DOP receptor.

In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according to the invention have agonist activity at the MOP receptor, agonist activity at the KOP receptor, and antagonist activity at the DOP receptor. In some embodiments, preferably with respect to receptors of the peripheral nervous system, the compounds according, to the invention

-   -   have agonist activity at the MOP receptor as well as agonist         activity at the KOP receptor as well as antagonist activity at         the DOP receptor;     -   have agonist activity at the MOP receptor as well as agonist         activity at the KOP receptor as well as antagonist activity at         the DOP receptor as well as agonist activity at the NOP         receptor;     -   have agonist activity at the MOP receptor as well as agonist         activity at the KOP receptor as well as antagonist activity at         the DOP receptor as well as antagonist activity at the NOP         receptor; or     -   have agonist activity at the MOP receptor as well as agonist         activity at the KOP receptor as well as antagonist activity at         the DOP receptor, no significant activity at the NOP receptor.

In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention have selective agonist activity at the NOP receptor. In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention

-   -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the KOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the DOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor;     -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the DOP receptor; or     -   have agonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor as well as no significant activity at the         DOP receptor.

In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention have selective antagonist activity at the NOP receptor. In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention

-   -   have antagonist activity at the NOP receptor, but no significant         activity at the MOP receptor;     -   have antagonist activity at the NOP receptor, but no significant         activity at the KOP receptor;     -   have antagonist activity at the NOP receptor, but no significant         activity at the DOP receptor;     -   have antagonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor;     -   have antagonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the DOP receptor; or     -   have antagonist activity at the NOP receptor, but no significant         activity at the MOP receptor as well as no significant activity         at the KOP receptor as well as no significant activity at the         DOP receptor.

In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention have antagonist activity at the NOP receptor as well as agonist activity at the DOP receptor. In some embodiments, preferably with respect to receptors of the central nervous system, the compounds according to the invention

-   -   have antagonist activity at the NOP receptor as well as agonist         activity at the DOP receptor;     -   have antagonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         MOP receptor;     -   have antagonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         KOP receptor; or     -   have antagonist activity at the NOP receptor as well as agonist         activity at the DOP receptor, but no significant activity at the         MOP receptor as well as no significant activity at the KOP         receptor.

For the purpose of the specification, “no significant activity” means that the activity (agonist/antagonist) of the given compound at this receptor is lower by a factor of 1000 or more compared to its activity (agonist/antagonist) at one or more of the other opioid receptors.

A further aspect of the invention relates to the compounds according to the invention as medicaments.

A further aspect of the invention relates to the compounds according to the invention for use in the treatment of pain. A further aspect of the invention relates to a method of treating pain comprising the administration of a pain alleviating amount of a compound according to the invention to a subject in need thereof, preferably to a human. The pain is preferably acute or chronic. The pain is preferably nociceptive or neuropathic.

A further aspect of the invention relates to the compounds according to the invention for use in the treatment of neurodegenerative disorders, neuroinflammatory disorders, neuropsychiatric disorders, and substance abuse/dependence. A further aspect of the invention relates to a method of treating any one of the aforementioned disorders, diseases or conditions comprising the administration of a therapeutically effective amount of a compound according to the invention to a subject in need thereof, preferably to a human.

Another aspect of the invention relates to a pharmaceutical composition which contains a physiologically acceptable carrier and at least one compound according to the invention.

Preferably, the composition according to the invention is solid, liquid or pasty; and/or contains the compound according to the invention in an amount of from 0.001 to 99 wt. %, preferably from 1.0 to 70 wt. %, based on the total weight of the composition.

The pharmaceutical composition according to the invention can optionally contain suitable additives and/or auxiliary substances and/or optionally further active ingredients.

Examples of suitable physiologically acceptable carriers, additives and/or auxiliary substances are fillers, solvents, diluents, colorings and/or binders. These substances are known to the person skilled in the art (see H. P. Fiedler, Lexikon der Hilfsstoffe fur Pharmazie, Kosmetik and angrenzende Gebiete, Editio Cantor Aulendoff).

The pharmaceutical composition according, to the invention contains the compound according to the invention in an amount of preferably from 0.001 to 99 wt. %, more preferably from 0.1 to 90 wt. %, yet more preferably from 0.5 to 80 wt. %, most preferably from 1.0 to 70 wt. c′/′) and in particular from 2.5 to 60 wt. %, based on the total weight of the pharmaceutical composition.

The pharmaceutical composition according to the invention is preferably for systemic, topical or local administration, preferably for oral administration.

Another aspect of the invention relates to a pharmaceutical dosage form which contains the pharmaceutical composition according to the invention.

In one preferred embodiment, the pharmaceutical dosage form according to the invention is produced for administration twice daily, for administration once daily or for administration less frequently than once daily. Administration is preferably systemic, in particular oral.

The pharmaceutical dosage form according to the invention can be administered, for example, as a liquid dosage form in the form of injection solutions, drops or juices, or as a semi-solid dosage form in the form of granules, tablets, pellets, patches, capsules, plasters/spray-on plasters or aerosols. The choice of auxiliary substances etc. and the amounts thereof to be used depend on whether the form of administration is to be administered orally, perorally, parenterally, intravenously, intraperitoneally, intradermally, intramuscularly, intranasally, buccally, rectally or locally, for example to the skin, the mucosa or into the eyes.

Pharmaceutical dosage forms in the form of tablets, dragees, capsules, granules, drops, juices and syrups are suitable for oral administration, and solutions, suspensions, readily reconstitutable dry preparations and also sprays are suitable for parenteral, topical and inhalatory administration. Compounds according to the invention in a depot, in dissolved form or in a plaster, optionally with the addition of agents promoting penetration through the skin, are suitable percutaneous administration preparations.

The amount of the compounds according to the invention to be administered to the patient varies in dependence on the weight of the patient, on the type of administration, on the indication and on the severity of the disease. Usually, from 0.00005 mg/kg to 50 mg/kg, preferably from 0.001 mg/kg to 10 mg/kg, of at least one compound according to the invention is administered.

Another aspect of the invention relates to a process for the preparation of the compounds according to the invention. Suitable processes for the synthesis of the compounds according to the invention are known in principle to the person skilled in the art.

Preferred synthesis routes are described below:

The compounds according to the invention can be obtained via different synthesis routes. Depending on the synthesis route, different intermediates are prepared and subsequently further reacted.

In a preferred embodiment, the synthesis of the compounds according to the invention proceeds via a synthesis route which comprises the preparation of an intermediate according to general formula (IIIa):

wherein R¹, R² and R³ are defined as above.

In another preferred embodiment, the synthesis of the compounds according to the invention proceeds via a synthesis route which comprises the preparation of an intermediate according to general formula (IIIb):

wherein R¹, R² and R³ are defined as above and PG is a protecting group.

Preferably the protecting group is -p-methoxybenzyl. Therefore, in another preferred embodiment, the synthesis of the compounds according to the invention proceeds via a synthesis route which comprises the preparation of an intermediate according to general formula (IIIc):

wherein R¹, R² and R³ are defined as above.

As already indicated, in general formula (IIIc), the -p-methoxybenzyl moiety represents a protecting group which can be cleaved in the course of the synthesis route.

In yet another preferred embodiment, the synthesis of the compounds according to the invention proceeds via a synthesis route which comprises the preparation of

-   -   an intermediate according to general formula (IIIa) and         according to general formula (IIIb); or     -   an intermediate according to general formula (IIIa) and         according to general formula (IIIc); or     -   an intermediate according to general formula (IIIb) and         according to general formula (IIIc); or     -   an intermediate according to general formula (IIIa), according         to general formula (IIIb) and according to general formula         (IIIc).

The following examples further illustrate the invention but are not to be construed as limiting its scope.

EXAMPLES

“RT” means room temperature (23±7° C.), “M” are indications of concentration in mol/l, “aq.” means aqueous, “sat.” means saturated, “sol.” means solution, “conc.” means concentrated.

Further abbreviations:

-   brine saturated aqueous sodium chloride solution -   CC column chromatography -   cHex cyclo hexane -   DCM dichloromethane -   DIPEA N,N-diisopropylethylamine -   DMF N,N-dimethylformamide -   Et Ethyl -   ether diethyl ether -   EE ethyl acetate -   EtOAc ethyl acetate -   EtOH ethanol -   le hour(s) -   H₂O water -   HATU     O-(7-aza-benzotriazol-1-yl)-N,N,N′,N″-tetramethyluroniumhexafluorophosphate -   LDA Lithium-di-isoproyl-amid -   Me Methyl -   m/z mass-to-charge ratio -   MeOH methanol -   MeCN acetonitrile -   min minutes -   MS mass spectrometry -   NBS N-bromo-succinimide -   NEt₃ triethyl amine -   Pd₂(dba)₃ tris(dibenzylideneacetone)dipalladium(0) -   PE Petrol Ether (60-80° C.) -   RM reaction mixture -   RT room temperature -   T3P     2,4,6-Tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide -   tBME tert-.butyl methyl ether -   THF tetrahydrofuran -   v/v volume to volume -   w/w weight to weight -   XantPhos 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene

The yields of the compounds prepared were not optimised. All temperatures are uncorrected.

All starting materials, which are not explicitly described, were either commercially available (the details of suppliers such as for example Acros, Aldrich, Bachem, Butt park, Enamine, Fluka, Lancaster, Maybridge, Merck, Sigma, TCI, Oakwood, etc. can be found in the Symyx® Available Chemicals Database of MDL, San Ramon, US or the SciFinder® Database of the ACS, Washington D.C., US, respectively, for example) or the synthesis thereof has already been described precisely in the specialist literature (experimental guidelines can be found in the Reaxys® Database of Elsevier, Amsterdam, NL or the SciFinder® Database of the ACS, Washington D.C., US, respectively, for example) or can be prepared using the conventional methods known to the person skilled in the art.

The mixing ratios of solvents or ducats for chromatography are specified in v/v.

All the intermediate products and exemplary compounds were analytically characterised by mass spectrometry (MS, m/z, for [M+H]⁺). In addition ¹H-NMR and ¹³C spectroscopy was carried out for all the exemplary compounds and selected intermediate products.

Remark Regarding Stereochemistry

CIS refers to the relative configuration of compounds described herein, in which both nitrogen atoms are drawn on the same face of the cyclohexane ring as described in the following exemplary structure. Two depictions are possible:

TRANS refers to compounds, in which both nitrogen atoms are on opposite faces of the cyclohexane ring as described in the following exemplary structure. Two depictions are possible:

Synthesis of Intermediates Synthesis of INT-799: CIS-8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-1-((1-(benzyloxy)cyclobutyl)methyl)-3-(3,4-dimethoxybenzyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

NaOH (1.42 g, 35.5 mmol) was added to a solution of CIS-3-(3,4-dimethoxybenzyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-794) (3 g, 7.09 mmol) in DMSO (90 mL) under argon atmosphere and the reaction mixture was stirred at 80° C. for 30 min. ((1-(Bromomethyl)cyclobutoxy)methyl)benzene (5.4 g, 21.3 mmol) was added and stirring was continued for 2 days at 80° C. The reaction completion was monitored by TLC. The reaction mixture was diluted with water (500 mL) and extracted with diethyl ether (4×300 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The residue was purified by column chromatography (230-400 mesh silica gel; 65-70% EtOAc in petroleum ether as eluent) to afford 2.5 g (59%) of CIS-1-((1-(benzyloxy)cyclobutyl)methyl)-3-(3,4-dimethoxybenzyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (TLC system: 10% MeOH in DCM; Rf: 0.8).

Step 2: CIS-8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

TFA (12 mL) was added to CIS-1-((1-(benzyloxy)cyclobutyl)methyl)-3-(3,4-dimethoxybenzyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (2.5 g, 4.18 mmol) at 0° C. and the resulting mixture was stirred at 70° C. for 6 h. The reaction completion was monitored by LCMS. The reaction mixture was concentrated under reduced pressure. To the residue sat. aq. NaHCO₃ was added (until pH 10) and the organic product was extracted with DCM (3×150 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The residue was purified by column chromatography (230-400 mesh silica gel; 5% MeOH in DCM as eluent) to afford 500 mg (33%) of CIS-8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-799) (TLC system: 10% MeOH in DCM; Rf: 0.5). [M+H]⁺ 358.2

Synthesis of INT-897: CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionic acid

Step 1: CIS-3-(1-(cyclobutylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile

KOtBu (1.7 g, 15.23 mmol) was added to a suspension of CIS-1-(cyclobutyl-methyl)-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-987) (1.3 g, 3.80 mmol) in DMSO (20 mL) at RT. 3-Bromo-2,2-dimethylpropanenitrile (3.7 g, 28.84 mmol) was added and the reaction mixture was stirred for 16 h at 130° C. The reaction mixture was quenched with cold water (25 mL) and the organic product was extracted with EtOAc (2×20 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to give 1.6 g of CIS-3-(1-(cyclobutylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile as a brown semi-solid. (TLC system: 10% MeOH in DCM; Rf: 0.6), The product was used in the next step without further purification.

Step 2: CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionic acid

12 N aq. HCl (16 mL) was added to CIS-3-(1-(cyclobutylmethyl)-8-(dimethylamino)-2-exo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (1.6 g, 3.78 mmol) and the resulting solution was refluxed for 16 h. The reaction mixture was concentrated under reduced pressure. To the residue toluene was added and the resulting mixture was concentrated under reduced pressure again. Tire residue was washed with acetone (10 mL), diethyl ether (10 mL) and DCM (10 mL) to give 1.2 g of CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionic acid (INT-897) as a solid. (TLC system: 10% MeOH in DCM R_(f): 0.3) [M+H]⁺ 442.3

Synthesis of INT-898: CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid; 2,2,2-trifluoro-acetic acid salt

Step 1: CIS-tert-butyl-3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate

KOtBu (1M in THF) (13.74 mL, 13.74 mmol) was added to a solution of CIS-1-(cyclobutyl-methyl)-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-987) (2.5 g, 9.16 mmol) in 1,4-dioxane (240 mL) under argon atmosphere and the reaction mixture was stirred for 15 minutes. Tert-butyl acrylate (1.60 mL, 10.99 mmol) in 1,4-dioxane (10 mL) was added. The reaction mixture was stirred for 1 h at RT, then quenched with sat. aq. NH₄Cl (60 mL) and the organic product was extracted with EtOAc (2×100 mL). The combined organic layer was dried over anhydr. Na₂SO₄ and concentrated in vacuo. The crude product was purified by column chromatography (using 100-200 mesh silica gel and 0-10 vol % MeOH, in DCM as eluent) to afford 1.2 g (32%) of tert-butyl CIS-3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate as pale yellow solid (TLC system: 10% MeOH in DCM; Rf: 0.4).

Step 2: CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid; 2,2,2-trifluoro-acetic acid salt

CIS-tert-butyl-3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate (44 mg) was treated with TEA (360 pt) at RT for 30 min. All volatiles were removed in vacuo. The residue was taken up in toluene and concentrated under reduced pressure (3×) to yield 3-(cis-1-(cyclobutylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl) propanoic acid as the trifluoroacetic acid salt (INT-898) (54 mg). [M+H]⁺ 414.3

Synthesis of INT-899: CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid

Step 1: CIS-tert-butyl 3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate

In analogy to the method described for INT-898 step 1 CIS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-976) was converted into CIS-tert-butyl 3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate.

Step 2: CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid

A mixture of CIS-tert-butyl 3-(8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanoate (2.2 g, 5.486 mmol) and powdered NaOH (877 mg, 21.95 mmol) in toluene (40 mL) was stirred at 80° C. for 5 h under argon atmosphere. Toluene was evaporated in vacuo. The resulting off-white solid, was dissolved in DMSO (40 mL) under argon atmosphere at RT and powdered NaOH (877 mg, 21.945 mmol) was added in one portion. The reaction mixture was stirred at 55° C. for 1 h. (1-(tert-butyldimethylsilyloxy)cyclobutyl)methyl 4-methylbenzenesulfonate (2.029 g, 5.486 mmol) was added dropwise over 5 min. The reaction mixture was stirred for 1.5 h at 55° C. and a new portion of (1-(tert-butyldimethylsilyloxy)cyclobutyl)methyl 4-methylbenzenesulfonate (2.029 g, 5.486 mmol) was added dropwise over 5 Min. Stirring was continued at 55° C. for 18 h. (1-(tert-butyldimethylsilyloxy)cyclobutyl)methyl 4-methylbenzenesulfonate (2.029 g, 5.486 mmol) was added dropwise over 5 min and stirring was continued for 65 h at 55° C. The reaction progress was monitored by LCMS. DMSO was evaporated in vacuo. The resulting crude product was dissolved in water (50 mL), the solution was cooled to 0° C. and, neutralized with acetic acid. The excess water was evaporated in vacuo and the residue was purified by column chromatography (using 100-200 mesh silica gel and 0-10 vol % MeOH in DCM as an eluent) to get 450 mg of CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid (INT-899) contaminated with 4-methylbenzene-sulfonic acid (44% pure by LCMS) as a pale yellow solid. This material was used for following reactions without additional purification. [M+H]⁺ 430.3

Synthesis of INT-951: CIS-1-[(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-methyl]-cyclobutane-1-carbonitrile

Step 1: 1-((CIS-8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-8-phenyl-1,3-diazaspiro[1.5]decan-1-yl)methyl)cyclobutanecarbonitrile

NaH (50% in mineral oil) (2.44 g, 50.89 mmol) was added to a solution of CIS-8-dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) (5 g, 12.72 mmol) in DMF (100 mL) at 0° C. portionwise over 10 min. 1-(Bromomethyl)cyclobutanecarbonitrile (4.4 g, 25.44 mmol) was added dropwise over 10 minutes at 0° C. The reaction mixture was allowed to stir at RT for 3 h, then quenched with water and the organic product was extracted with ethyl acetate (3×200 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford 5 g (crude) of 1-((CIS-8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl) methy 1)cyclobutane-carbonitrile as gummy brown liquid. The material was used for the next step without further purification.

Step 2: 1-((CIS-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)methyl) cyclobutanecarboxamide

TFA (100 mL) was added to 1-((CIS-8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)methyl)cyclobutanecarbonitrile (5 g, 10.28 mmol) at 0° C. and the reaction mixture at mixture was stirred at RT for 2 days. The reaction mixture was concentrated in vacuo. To the residue sat. aq. NaHCO₃ was added (until pH 10) and the organic product was extracted with dichloromethane (3×150 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford 3.5 g (crude) of -((CIS-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)methyl) cyclobutanecarboxamide. The material was used for the next step without further purification.

Step 3: 1-((cis-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)methyl)cyclobutane carbonitrile

Thionyl chloride (35 mL) was added to 1-((cis-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)methyl)cyclobutanecarboxamide (3.5 g, 9.11 mmol) at RT and the resulting mixture was stirred at reflux for 2 h. The reaction mixture was concentrated in vacuo. To the residue sat. aq. NaHCO₃ was added (until pH 10) and the organic product was extracted with dichloromethane (3×150 mL). The combined organic layer was (hied over anhydrous Na₂SO₄ and concentrated in vacuo. The residue was purified by column chromatography to afford 1.3 g (34% after three steps) of CIS-1-[(8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-methyl]-cyclobutane-1-carbonitrile (INT-951). [M+H]⁺ 367.2.

Synthesis of INT-952: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-phenyl-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

To a solution of CIS-8-dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) (10 g, 25 mmol) THF (500 mL) was added KOtBu (7.1 g, 63 mmol) at 50° C. The reaction mixture was heated up to reflux, cyclobutylmethylbromide (11.3 g, 76 mmol) was added in one portion, and stirring was continued at reflux for 12 h. KOtBu (7.1 g) and cyclobutylmethylbromide (11.3 g) were added again. The reaction mixture was allowed to stir another 2 h at reflux, then cooled to RT, diluted with water (150 mL) and the layers partitioned. The aqueous layer was extracted with EtOAc (3×300 mL). The combined organic layers were dried over Na₂SO₄ and then concentrated in vacuo. The residue was filtered through a plug of silica gel using a DCM/MeOH (19/1 v/v) mixture. The filtrate was concentrated in vacuo and the resulting solid, was recrystallized from hot ethanol to yield 7.8 g of CIS-1-(cyclobutyl-methyl)-8-dimethylamino-8-phenyl-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-952). [M+H]⁺ 461.3.

Synthesis of INT-953: CIS-1-(Cyclobutyl-methyl)-8-(methyl-(2-methyl-propyl)-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: 1-Cyclobutylmethyl-3-(4-methoxy-benzyl)-9,12-dioxa-1,3-diaza-dispiro[4.2.4.2]tetradecan-2-one

To a stirred solution of 3-(4-methoxy-benzyl)-9,12-dioxa-1,3-diaza-dispiro[4.2.4.2]tetradecan-2-one (4 g, 12.04 mmol) in anhydrous DMF (60 ml) was added NaH (1.38 g, 60% dispersion in oil, 36.14 mmol) at RT. The reaction mixture was stirred for 10 min, bromomethylcyclobutane (3 nil, 26.5 mmol) was added dropwise and stirring was continued for 50 h. TLC analysis showed complete consumption of the starting material. The reaction mixture was quenched with sat. aq. NH₄Cl (50 ml) and extracted with EtOAc (3×200 ml). The combined organic phase was dried over Na₂SO₄ and concentrated, under reduced pressure. Time resulting residue was purified column chromatography (neutral aluminum oxide, EtOAc—petroleum ether (2:8)) to give 1-cyclobutylmethyl-3-(4-methoxy-benzyl)-9,12-dioxa-1,3-diaza-dispiro[4.2.4.2]tetradecan-2-one (2.4 g, 50%, white solid). TLC system: EtOAc—pet ether (6:4); R_(f)=048.

Step 2: 1-Cyclobutylmethyl-3-(4-methoxy-benzyl)-1,3-diazaspiro[4.5]decane-2,8-dione

To a stirred solution of 1-cyclobutylmethyl-3-(4-methoxy-benzyl)-9,12-dioxa-1,3-diaza-dispiro[4.2.4.2]tetradecan-2-one (1 g, 2.5 mmol) in MeOH (7 ml) was added 10% aq. HCl (8 ml) at 0° C. The reaction mixture was warmed up to RT and stirred for 16 h. TLC analysis showed complete consumption of the starting material. The reaction mixture was quenched with sat. aq. NaHCO₃ (30 ml) and extracted with EtOAc (3×50 ml). The combined organic phase was dried over Na₂SO₄ and concentrated under reduced pressure. The resulting residue was purified by column chromatography (silica gel, 230-400 mesh, EtOAc—pet ether (1:3)→(3:7)) to give 1-cyclobutylmethyl-3-(4-methoxy-benzyl)-1,3-diazaspiro[4.5]decane-2,8-dione (650 mg, 73%, colorless viscous oil). TLC system: EtOAc—pet ether (6:4); R_(f)=0.40.

Step 3: 1-(cyclobutylmethyl)-8-(isobutyl(methyl)amino)-3-(4-methoxybenzyl)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile

To a stirred solution of N-isobutyl-N-methylamine (1.34 ml, 11.23 mmol) and MeOH/H₂O (8 ml, v/v) was added 4N aq. HCl (1.5 ml) and the reaction mixture was stirred for 10 min at 0° C. (ice bath). A solution of 1-cyclobutylmethyl-3-(4-methoxy-benzyl)-1,3-diazaspiro[4.5]decane-2,8-dione g, 2.80 mmol) in MeOH (7 ml) and KCN (548 mg, 8.42 mmol) were added and the reaction mixture was stirred at 45° C. for 20 h. TLC analysis showed complete consumption of the starting material. The reaction mixture was diluted with water (30 ml), extracted with EtOAc (3×30 ml), the combined organic phase was dried, over Na₂SO₄ and concentrated under reduced pressure to give 1-(cyclobutylmethyl)-8-(isobutyl)methyl)amino)-3-(4-methoxybenzyl)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (1.3 g, viscous yellow oil). TLC system: EtOAc—pet ether (1:1); R_(f)=0.45. The product was used for the next step without additional purification.

Step 4: CIS-1-(cyclobutylmethyl)-8-(isobutyl(methyl)amino)-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

A round bottom flask containing 1-(cyclobutylmethyl)-8-(isobutyl(methyl)amino)-3-(4-methoxybenzyl)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (1.3 g, 2.81 mmol) was cooled in an ice bath (˜0° C.) and a solution of phenylmagnesium bromide (26 ml, ˜2M in THF) was added slowly at 0° C.-5° C. The ice bath was removed and the reaction mixture was stirred for 30 min, then diluted with sat. aq. NH₄Cl (25 ml) and extracted with EtOAc (4×30 ml). The combined organic phase was dried over Na₂SO₄ and concentrated under reduced pressure to give pale yellow viscous oil. This residue was purified by column chromatography (silica gel, 230-400 mesh, eluent: EtOAc—pet ether (15:85)→(2:4)) to give CIS-1-(cyclobutylmethyl)-8-(isobutyl(methyl)amino)-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (135 mg, 10%, white solid). TLC system: EtOAc—pet ether (1:1); R_(f)=0.6

Step 5: CIS-1-(Cyclobutyl-methyl)-8-(methyl-(2-methyl-propyl)-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

A round bottom flask containing CIS-1-(cyclobutylmethyl)-8-(isobutyl(methyl)amino)-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (130 mg, 0.25 mmol) was cooled in an ice bath and a mixture of TFA/CH₂Cl₂ (2.6 ml, 1:1, v/v) was added slowly at 0° C.-5° C. The reaction mixture was warmed to RT and stirred for 20 h, then quenched with methanolic NH₃ (10 ml, ˜10% in MeOH) and concentrated under reduced pressure to give pale yellow viscous oil. This residue was purified twice by column chromatography (silica gel, 230-400 mesh, eluent: MeOH—CHCl₃ (1:99)→(2:98)) to give CIS-1-(cyclobutyl-methyl)-8-(methyl-(2-methyl-propyl)-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-953) (65 mg, 66%, white solid). TLC system: MeOH—CHCl₃ (5:95); R_(f)=0.25; [M+H]⁺ 384.3

Synthesis of INT-958: 4-Oxo-1-pyridin-2-yl-cyclohexane-1-carbonitrile

Step 1: Ethyl 5-cyano-2-oxo-5-(pyridin-2-yl)cyclohexanecarboxylate

KOtBu (57.0 g, 508.4 mmol) was added to the solution of 2-(pyridin-2-yl)acetonitrile (50.0 g, 423.7 mmol) and ethyl acrylate (89.0 g, 889.8 mmol) in THF (500 mL) at 0° C. and stirred for 16 h at RT. The reaction mixture was quenched with sat. aq. NH₄Cl and extracted with EtOAc (2×500 mL). The combined organic layer was washed with brine, dried over Na₂SO₄ and concentrated under reduced pressure to afford 68.0 g (60%; crude) of ethyl 5-cyano-2-oxo-5-(pyridin-2-yl)cyclohexanecarboxylate as a brown liquid (TLC system: 50% ethyl acetate in petroleum ether; Rf: 0.65).

Step 2: 4-Oxo-1-pyridin-2-yl-cyclohexane-1-carbonitrile

A solution of ethyl 5-cyano-2-oxo-5-(pyridin-2-yl)cyclohexanecarboxylate (68.0 g, 250.0 mmol) was added to a mixture of conc. aq. HCl and glacial acetic acid (170 mL/510 mL) cat 0° C. The reaction mixture was heated to 100° C. for 16 It. All volatiles were evaporated under reduced pressure. The residue was diluted with sat. aq. NaHCO₃ and extracted with ethyl acetate (3×300 mL). The combined organic layer was washed with brine, dried over Na₂SO₄ and concentrated under reduced pressure to afford 44.0 g (88%) of 4-oxo-1-pyridin-2-yl-cyclohexane-1-carbonitrile INT-958 as a brown solid (TLC system: 50% ethyl acetate in pet ether; Rf: 0.45). [M+H]⁺ 201.1

Synthesis of INT-961: 4-Dimethylamino-4-pyridin-2-yl-cyclohexan-1-one

Step 1: 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decane-8-carbonitrile

A solution of 4-oxo-1-pyridin-2-yl-cyclohexane-1-carbonitrile (INT-958) (44.0 g, 220.0 mmol), ethylene glycol (27.0 g, 440.0 mmol) and PTSA (4.2 g, 22.0 mmol) in toluene (150 mL) was heated to 120° C. for 16 h using Dean Stark apparatus. All volatiles were evaporated under reduced pressure. The residue was diluted with sat. aq. NaHCO₃ and extracted with ethyl acetate (3×300 mL). The combined organic layer was washed with brine, dried over Na₂SO₃ and concentrated under reduced pressure to afford 45.0 g (85%) of 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decane-8-carbonitrile as a light brown solid (TLC system: 50% ethyl acetate in petroleum ether; Rf: 0.55).

Step 2: 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decane-8-carboxamide

Potassium carbonate (50.0 g, 368.84 mmol) and 30% aq, H₂O₂ (210.0 mL, 1844.2 mmol) were added to the solution of 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decane-8-carbonitrile (45.0 g, 184.42 mmol) in DMSO (450 mL) at 0° C. and the resulting mixture was stirred at RT for 14 h. The reaction mixture was diluted with water (1.5 L) and stirred fort h. The precipitated solid was separated by filtration, washed with water, petroleum ether and dried under reduced pressure to get 32.0 g (66%) of 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-carboxamide as a white solid. (TLC system: 10% MeOH in DCM R_(f): 0.35).

Step 3: methyl 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-ylcarbamate

A mixture of 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decane-8-carboxamide (25.0 g, 95.41 mmol), sodium hypochlorite (5 wt % aq. solution, 700 mL, 477.09 mmol) and KF—Al₂O₃ (125.0 g) in methanol (500 mL) was heated to 80° C. for 16 h. The reaction mixture was filtered through celite and the solid residue was washed with methanol. The combined filtrate was concentrated under reduced pressure. The residue was diluted with water and extracted with ethyl acetate (3×500 mL). The combined organic layer was washed with brine, dried over Na₂SO₄ and concentrated under reduced pressure to afford 18.0 g (66%) of methyl 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-ylcarbamate as a light brown solid. (TLC system: 5% MeOH in DCM R_(f): 0.52.)

Step 4: 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-amine

A suspension of methyl 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-ylcarbamate (18.0 g, 61.64 mmol) in 10 wt % aq. NaOH (200 mL) was heated to 100° C. for 24 h. The reaction mixture was filtered through celite pad, the solid residue was washed with water and the combined filtrate was extracted with EtOAc (4×200 mL), The combined organic layer washed with brine, dried over Na₂SO₄ and concentrated under reduced pressure to afford 12.5 g (88%) of 8-(pyridin-2-yl)-14-dioxaspiro[4.5]decan-8-amine as a light brown semi-solid. (TLC system: 5% MeOH in DCM R_(f): 0.22.).

Step 5: 4-Dimethylamino-4-pyridin-2-yl-cyclohexan-1-one

Sodium cyanoborohydride (13.7 g, 0.213 mol) was added portionwise to a solution of 8-(pyridin-2-yl)-1,4-dioxaspiro[4.5]decan-8-amine (12.5 g, 53.418 mmol) and 35 wt % aq. formaldehyde (45 mL, 0.534 mol) in acetonitrile (130 mL) at 0° C. The reaction mixture was warmed up to room temperature and stirred for 16 h. The reaction mixture was quenched with sat. aq. NH₄Cl and concentrated under reduced pressure. The residue was dissolved in water and extracted with EtOAc (3×200 mL). The combined organic layer was washed with brine, dried over Na₂SO₄ and concentrated trader reduced pressure to afford 10.5 g (72%) of 4-dimethylamino-4-pyridin-2-yl-cyclohexan-1-one (INT-961) as a light brown solid. (TLC system: 5% MeOH in DCM R_(f): 0.32.). [M+H]⁺ 219.1

Synthesis of INT-965: 4-Dimethylamino-4-phenyl-cyclohexan-1-one

Step 1: 8-(Dimethylamino)-1,4-dioxaspiro 4.5]decane-8-carbonitrile

Dimethylamine hydrochloride (52 g, 0.645 mol) was added to the solution of 1,4-dioxaspiro-[4.5]-decan-8-one (35 g, 0.224 mmol) in MeOH (35 mL) at RT under argon atmosphere. The solution was stirred for 10 min and 40 wt % aq. dimethylamine (280 mL, 2.5 mol) and KCN (32 g, 0.492 mol) were sequentially added. The reaction mixture was stirred for 48 h at RT, then diluted with water (100 mL) and extracted with EtOAc (2×200 mL). The combined organic layer was dried, over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford 44 g of 8-(dimethylamino)-1,4-dioxaspiro-[4.5]-decane-8-carbonitrile (93%) as a white solid.

Step 2: N,N-dimethyl-8-phenyl-1,4-dioxaspiro[4.5]decan-8-amine

8-(Dimethylamino)-1,4-dioxaspiro[4.5]decane-8-carbonitrile (35 g, 0.167 mol) in THF (350 mL) was added to the solution of 3M phenylmagnesium bromide in diethyl ether (556 mL, 1.67 mol) dropwise at −10′C under argon atmosphere. The reaction mixture was stirred for 4 h at −10° C. to 0° C. and then at RT for 18 h. The reaction completion was monitored by TLC. The reaction mixture was cooled to 0° C., diluted with sat. aq. NH₄Cl (1 L) and extracted with EtOAc (2×600 mL). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford 60 g of, N N-dimethyl-8-phenyl-1,4-dioxaspiro-[4.5]-decan-8-amine as a liquid.

Step 3: 4-(dimethylamino)-4-phenylcyclohexanone

A solution of N,N-dimethyl-8-phenyl-1,4-dioxaspiro[4.5]decan-8-amine (32 g, 0.123 mol) in 6N aq. HCl (320 mL) was stirred at 0° C. for 2 h and then at RT for 18 h. The reaction completion was monitored by TLC. The reaction mixture was extracted with DCM (2×150 mL). The aqueous layer was basified to pH 10 with solid NaOH and extracted with ethyl acetate (2×200 mL). The confined organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The solid residue was washed with hexane and dried in vacuo to afford 7 g of 4-dimethylamino-4-phenyl-cyclohexan-1-one (INT-965) (25% over 2 steps) as a brown solid. [M+H]⁺ 218.1

Synthesis of INT-966: 3-[(4-Methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decane-2,8-dione

Step 1: 9,12-Dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-dione

KCN (93.8 g, 1441.6 mmol) and (NH₄)₂CO₃ (271.8 g, 1729.9 mmol) were added to the solution of 1,4-dioxaspiro[4.5]decan-8-one (150 g, 961 mmol) in MeOH:H₂O (1:1 v/v) (1.92 L) at RT under argon atmosphere. The reaction mixture was stirred at 60° C. for 16 h. The reaction completion was monitored by TLC. The reaction mixture was cooled to 0° C., the precipitated solid was filtered off and dried in vacuo to afford 120 g (55%) of 9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-dione. The filtrate was extracted with DCM (2×1.5 L). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated, under reduced pressure to afford additional 30 g (14%) of 9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-dione (TLC system: 10% Methanol in DCM; Rf: 0.4).

Step 2: 2-[(4-Methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-dione

Cs₂CO₃ (258.7 g, 796 mmol) was added to the solution of 73a (150 g, 663.4 mmol) in MeCN (1.5 L) under argon atmosphere and the reaction mixture was stirred for 30 min. A solution of p-methoxybenzyl bromide (96 mL, 663.4 mmol) was added. The reaction mixture was stirred at RT for 48 h. The reaction completion was monitored by TLC. The reaction mixture was quenched with sat. aq. NH₄Cl (1.0 L) and the organic product was extracted with EtOAc (2×1.5 L). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The residue was washed with diethyl ether and pentane and dried under reduced pressure to afford 151 g (65%) of 2-[(4-Methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-dione as an off white solid (TLC system: 10% MeOH in DCM; Rf: 0.6).

Step 3: 2-[(4-Methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one

AlCl₃ (144.3 g, 1082.6 mmol) was added to a solution of LiAlH₄ (2M in THF) (433 mL, 866.10 mmol) THF (4.5 L) at 0° C. under argon atmosphere and the resulting mixture was stirred at RT for 1 h. 2-[(4-Methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecane-1,3-diene (150 g, 433.05 mmol) was added at 0° C. The reaction mixture was stirred at RT for 16 h. The reaction completion was monitored by TLC. The reaction mixture was cooled to 0° C., quenched with sat. aq. NaHCO₃ (500 mL) and filtered through celite pad. The filtrate was extracted with EtOAc (2×2.0 L). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated in vacuo to afford 120 g (84%) of 2-[(4-methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one as an off-white solid. (TLC system: 10% MeOH in DCM, Rf: 0.5).

Step 4: 3-[(4-Methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decane-2,8-dione

A solution of 2-[(4-methoxyphenyl)-methyl]-9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one (120 g, 361.03 mmol) in 6N aq. HCl (2.4 L) was stirred at 0° C. for 2 h and then at RT for 18 h. The reaction completion was monitored by TLC. The reaction mixture was extracted with DCM (2×2.0 L). The aqueous layer was basified to pH 10 with 50% aq. NaOH and then extracted with DCM (2×2.0 L). Combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The solid residue was washed with hexane and dried in vacuo to afford 90 g of 3-[(4-Methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decane-2,8-dione (INT-966) as an off-white solid (TLC system; 10% MeOH in DCM; Rf: 0.4) [M+H]⁺289.11.

Synthesis of INT-971: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-(3-hydroxyphenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-8-(dimethylamino)-1-isobutyl-3-(1-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method described for INT-951 step 1 CIS-8-Dimethylamino-8-[3-(methoxymethyloxy)-phenyl]-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-958) was converted into CIS-1-(cyclobutylmethyl)-8-(dimethylamino)-3-(4-methoxybenzyl)-8-(3 (methoxymethoxy)phenyl)-1,3-diazaspiro[4.5]decan-2-one.

Step 2: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-(3-hydroxyphenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

TFA (0.2 mL) was added to the solution of CIS-1-(cyclobutylmethyl)-8-(dimethylamino)-3-(4-methoxybenzyl)-8-(3-methoxyphenyl)-1,3-diazaspiro[4.5]decan-2-one (300 mg, 0.57 mmol) in DCM (1.5 mL) at 0° C. The reaction mixture was stirred at 0° C. for 3 h. The reaction completion was monitored by TLC. The reaction mixture was quenched with sat. aq. NaHCO₃ and the organic product was extracted with DCM (3×1.0 mL). The combined organic extracts were dried, over anhydrous Na₂SO₄ and concentrated under reduced pressure. Purification of the residue by preparative TLC (3% MeOH in DCM as mobile phase) yielded 50 mg (18%) of CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-(3-hydroxyphenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-971) as an off white solid. (TLC system: 10% MeOH in DCM; Rf: 0.20) [M+H]⁺ 478.3

Synthesis of INT-974: CIS-8-Dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

Step 1: 8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-1,3-(diazaspiro[4.5]decane-8-carbonitrile

Dimethylamine hydrochloride (76.4 g, 936.4 mmol) was added to a solution of 3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decane-2,8-dione (INT-966) (91) g, 312.13 mmol) MeOH (180 mL) at RT under argon atmosphere. The solution was stirred for 15 ruin and 40 wt % aq. dimethylamine (780 mL) and KCN (48.76 g, 749.11 mmol) were sequentially added. The reaction mixture was stirred for 48 h and the completion of the reaction was monitored by NMR. The reaction mixture was diluted with water (1.0 L) and the organic product was extracted with ethyl acetate (2×2.0 L). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford 90 g (85%) of 8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile as an off white solid (TLC system: TLC system: 10% MeOH in DCM; Rf: 0.35, 0.30).

Step 2: CIS-8-Dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

3-Fluorophenylmagnesium bromide (1M in THE) (220 mL, 219.17 mmol) was added dropwise to a solution of 8-(dimethylamino)-3-(4-methoxybenzyl)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (15 g, 43.83 mmol) in THE (300 mL) at 0° C. under argon atmosphere. The reaction mixture was stirred for 16 h at RT. The reaction completion was monitored by TLC. The reaction mixture was cooled to 0° C., quenched with sat. aq. NH₄Cl (200 mL) and the organic product was extracted with EtOAc (2×200 mL). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The reaction was carried out in 4 batches (15 g×2 and 5 g×2) and the batches were combined for purification. Purification of the crude product by flash column chromatography on silica gel (230-400 mesh) (2 limes) (0-20% methanol in DCM) eluent and subsequently by washing with pentane yielded 5.6 g (11%) of CIS-8-dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-974) as an off-white solid (TLC system: 5% MeOH in DCM in presence of ammonia; Rf: 0.1). [M+H]⁺ 412.2

Synthesis of INT-975: CIS-8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

KOtBu (1M in THF) (29.30 mL, 29.30 mmol) was added to the solution of CIS-8-Dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one INT-976 (8.0 g, 29.30 mmol) in THE (160 mL) under argon atmosphere and the reaction mixture was stirred for 30 min. 4-Methoxybenzyl bromide (4.23 mL, 29.30 mmol) was added and stirring was continued at RT for 4 h. The reaction completion was monitored by TLC. The reaction mixture was diluted with sat. aq. NH₄Cl (150 mL) and the organic product was extracted with EtOAc (2×150 mL). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated in vacuo. The reaction was carried out in 2 batches (8 g×2) and the batches were combined for purification. Purification of the crude product by flash column chromatography on silica gel (0-10% methanol in DCM) and subsequently by washing with pentane yielded 11 g (47%) of CIS-8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) as a white solid, [M+H]⁺ 394.2

Synthesis of INT-976: CIS-8-Dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: 8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decane-2,4-dione

In a sealed tube 4-dimethylamino-4-phenyl-cyclohexan-1-one (INT-965) (2 g, 9.22 mmol) was suspended in 40 mL EtOH/H₂O (1:1 v/v) at RT under argon atmosphere. (NH₄)₂CO₃ (3.62 g, 23.04 mmol) and KCN (0.6 g, 9.22 mmol) were added. The reaction mixture was stirred at 60° C. for 18 h. The reaction mixture was cooled to 0° C. and diluted with ice-water and filtered through a glass filter. The solid residue was dried under reduced pressure to afford 8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decane-2,4-dione (1.8 g, 86%) as an off white crystalline solid (TLC: 80% EtOAc in hexane; Rf: 0.25).

Step 2: 8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decan-2-one

LiAlH₄ (2M in THF) (70 mL, 139.4 mmol) was added to the solution of 8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decane-2,4-dione (10 g, 34.8 mmol) in THF/Et₂O (2:1 v/v) (400 mL) at 0° C. under argon atmosphere. The reaction mixture was stirred for 4 h at 60° C. The reaction completion was monitored by TLC. The reaction mixture was cooled to 0° C., quenched with saturated Na₂SO₄ solution (100 mL) and filtered through Celite pad. The filtrate was dried over anhydrous Na₂SO₄ and concentrated in vacuo to afford 5.7 g (59%) of 8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decan-2-one as an off white solid. (TLC system: 10% MeOH in DCM, Rf: 0.3).

Step 3: CIS-8-Dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

A mixture of CIS- and TRANS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4,5]decan-2-one (8 g, 29.30 mmol) was purified by preparative chiral SEC (column: Chiralcel AS-H, 60% CO₂, 40% (0.5% DEA in MeOH)) to get 5 g of CIS-8-Dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-976) as a white solid. [M+H]⁺ 274.2.

Synthesis of INT-977: CIS-2-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-acetic acid; 2,2,2-trifluoro-acetic acid salt

Step 1: CIS-2-[8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl]-acetic acid tert-butyl ester

A solution of CIS-8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) (5.0 g, 12.7 mmol) THF (18 mL) was cooled to 0° C. and treated with LDA solution (2M in THF/heptane/ether, 25.4 mL, 50.8 mmol). The resulting mixture was allowed to warm up to RT over 30 min. The solution was then cooled to 0° C. again and tert-butyl-bromoacetate (5.63 mL, 38.1 mmol) was added. The reaction mixture was stirred at RT for 16 h, quenched with water and extracted with DCM (3×). The combinded organic layers were dried over Na₂SO₄, filtered and concentrated inder reduced pressure. Purification of the residue by column chromatography on silica gel provided CIS-2-[8-dimethylamino-3-[(4-methoxyphenyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl]-acetic acid tert-butyl ester (4.4 g).

Step 2: cis-2-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-acetic acid trifluoroacetic acid salt

CIS-2-[8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl]-acetic acid tert-butyl ester (200 rag, 0.4 mmol) was dissolved in TFA (5 mL) and heated to reflux overnight. After cooling to RT all volatiles are removed in vacuo. The residue was taken up in THF (1 and added dropwise to diethyl ether (20 mL). The resulting precipitate was filtered off and dried under reduced pressure to give CIS-2-(8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-acetic acid; 2,2,2-trifluoro-acetic acid salt (INT-977) (119 mg) as a white solid. [M+H]⁺ 332.2

Synthesis of INT-978: CIS-2-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-N,N-dimethyl-acetamide

CIS-2-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-acetic acid (INT-977) trifluoroacetic acid salt (119 mg, 0.35 mmol) was dissolved in DCM (5 mL). Triethylamine (0.21 mL, 1.6 mmol), dimethylamine (0.54 mL, 1.1 mmol) and T3P (0.63 mL, 1.1 mmol) were sequentially added. The reaction mixture was stirred at RT overnight, then diluted with 1 M aq. Na₂CO₃ (5 mL). The aqueous layer was extracted with DCM (3×5 mL), the combined organic layers were dried over Na₂SO₄ and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel to yield CIS-2-(8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-1-yl)-N,N-dimethyl-acetamide (INT-978) (39 mg) as a white solid. [M+H]⁺ 359.2

Synthesis of INT-982: CIS-8-Dimethylamino-1-[(1-methyl-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-8-(dimethylamino)-3-(4-methoxybenzyl)-1-((1-methylcyclobutyl)methyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

A solution of NaOH (2.85 g, 71.2 mmol) in DMSO (25 was stirred at RT for 10 min. CIS-8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) (7.00 g, 17.8 mmol) was added and stirring was continued for 15 min. 1-(Bromo-methyl)-1-methyl-cyclobutane (8.7 g, 53.4 mmol) was added at 0° C. The reaction mixture was heated to 60° C. for 16 h. After cooling down to RT, water (100 mL) was added and the mixture was extracted with DCM (3×150 The combined organic layers were washed with water (70 mL), brine (100 mL), dried over Na₂SO₄ and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel provided CIS-8-(dimethylamino)-3-(4-methoxybenzyl)-1-((1-methylcyclobutyl)methyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (6.5 g) as a light yellow solid.

Step 2: CIS-8-Dimethylamino-1-[(1-methyl-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

To the solution of CIS-8-Dimethylamino-1-[(1-methyl-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (6.66 g, 14.0 mmol) in DCM (65 mL) was added TFA (65 mL) and the resulting mixture was stirred at RT for 16 h. The reaction mixture was concentrated under reduced pressure. The residue was taken up in DCM (100 mL) and water (60 mL) and basified with 2M aq. NaOH to pH 10. The organic layer was separated and washed with brine (40 mL), dried over MgSO₄, filtered and concentrated under reduced pressure. Crystallization of the residue from EtOAc provided CIS-8-Dimethylamino-1-[(1-methyl-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-982) (3.41 g) as an off-white solid. [M+H]⁺ 356.3

Synthesis of INT-984: CIS-1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-8-(dimethylamino)-1-isobutyl-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method described for INT 951 step 1 CIS-8-Dimethylamino-3-[(4-methoxyphenyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-975) was converted into CIS-8-(dimethylamino)-1-isobutyl-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one.

Step 2: CIS-1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method described for INT-982 step 2 CIS-8-(dimethylamino)-1-isobutyl-3-(4-methoxybenzyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one was converted into CIS-1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-984).

Synthesis of INT-986: CIS-1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-3-benzyl-1-(cyclobutylmethyl)-8-(methylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

N-Iodosuccinimide (3.11 g, 13.92 mmol) was added to the solution of CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-phenyl-3-[phenyl-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-950) (4 g, 9.28 mmol) in a mixture of acetonitrile and THF (1:1 v/v, 80 mL) and the resulting mixture was stirred at RT for 16 h. The reaction mixture was basified with 2N aq. NaOH to pH˜10 and the organic product was extracted with DCM (3×10 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated in vacuo. The residue was stirred vigorously with a mixture of 10 wt % aq. citric acid (5 mL) and DCM (10 mL) at RT for 10 min. The reaction mixture was basified with 5N aq. NaOH to pH˜10 and extracted with DCM (3×10 mL). The combined organic layer was dried over anhydrous Na₂SO₁ and concentrated in vacuo to give 3.5 g (crude) of CIS-3-benzyl-1-(cyclobutylmethyl)-8-(methylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one as semi solid (TLC system: 10% MeOH in DCM; R_(f): 0.60.).

Step 2: CIS-3-benzyl-1-(cyclobutylmethyl)-8-(ethyl(methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Sodium cyanoborohydride (1.56 g, 25.17 mmol, 3 equiv.) was added to the solution of CIS-3-benzyl-1-(cyclobutylmethyl)-8-(methylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (3.5 g, 8.39 mmol), acetaldehyde (738 mg, 16.78 mmol, 2 equiv.) and acetic acid (0.5 mL) in methanol (20 mL). The reaction mixture was stirred at RT for 3 h, then quenched with sat. aq. NaHCO₃ and the organic product was extracted with DCM (3×50 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated in vacuo. Purification of the residue by flash column chromatography on silica gel (230-400 mesh) (20-25% ethyl acetate in petroleum ether) yielded 2.3 g (62%) of CIS-3-benzyl-1-(cyclobutylmethyl)-8-(ethyl(methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one as a solid. (TLC system: 50% EtOAc in Pet. Ether; R_(f): 0.65).

Step 3: CIS-1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-986)

Sodium metal (1.18 g, 51.68 mmol, 10 equiv.) was added to liquid ammonia (˜25 mL) at −78° C. The resulting mixture was stirred for 10 min at −78° C. A solution of CIS-3-benzyl-1-(cyclobutylmethyl)-8-(ethyl(methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (2.3 g, 5.16 mmol) in THF (25 mL) was added at −78° C. The reaction mixture was stirred for 15 min, then quenched with sat. aq. NH₄Cl, warmed to RT and stirred for 1 h. The organic product was extracted with DCM (3×50 mL). The combined organic layer was washed with water, brine and concentrated under reduced pressure to afford 1.30 g (72%) of CIS-1-(cyclobutylmethyl)-8-(ethyl(methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-986) as an off-white solid. (TLC system: 10% MeOH in DCM R_(f): 0.15.). [M+H]⁺ 356.3

Synthesis of INT-987: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method as described for INT-982 step 2 CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-phenyl-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-952) was converted into CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-987).

Synthesis of INT-1008: CIS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1 and step 2: ethyl-(8-phenyl-1,4-dioxa-spiro[4.5]dec-8-yl)-amine hydrochloride (ENT-1004)

A mixture of 1,4-dioxa-spiro[4.5]decan-8-one (25.0 g, 160.25 mmol, 1.0 eq.) and 2M solution of EtNH₂ in THF (200 ml, 2.5 eq. 400.64 mmol) in EtOH (30 mL) was stirred at RT for 48 h. The reaction mixture was concentrated under argon atmosphere. The residue was diluted with ether (60 mL) and added to the freshly prepared PhLi solution [prepared by addition of 2.5M n-BuLi in THF (70.5 mL, 1.1 eq. 176.27 mmol) to a solution of bromobenzene (27.675 g, 1.1 eq. 176.275 mmol) in ether (100 mL) at −30° C., and stirred at RT for 1 h] at RT. The reaction mixture was stirred at RT for 1.5 h, then cooled down to 0° C. and quenched with sat. aq. NH₄Cl (100 mL). The resulting mixture was extracted with EtOAc (2×750 mL), combined organic extracts were washed with water (3×350 mL), brine (300 mL), dried over Na₂SO₄ and concentrated under reduced pressure. The crude product was dissolved in ethylmethyl ketone (100 mL) and TMSCl (37.5 mL) was added at 0° C. The reaction mixture was stirred at RT for 16 h, the precipitate formed was filtered off and washed with acetone and THF to give ethyl-(8-phenyl-1,4-dioxa-spiro[4.5]dec-8-yl)-amine hydrochloride as an off-white solid. This reaction was done in 2 batches of 25 g scale and the yield is given for 2 combined batches. Yield: 18% (17.1 g, 57.575 mmol). LCMS: m/z 262.2 (M+H)⁺.

Step 3: 4-ethylamino-phenyl-cyclohexanone (INT-1005)

To a solution of ethyl-(8-phenyl-1,4-dioxa-spiro[4.5]dec-8-yl)-amine hydrochloride (10.1 g, 34.0 mmol, 1 eq.) in water (37.5 mL) was added conc. HCl (62.5 mL) at 0° C. and the reaction mixture was stirred at RT for 16 h. The reaction mixture was basified with 1N aq. NaOH to pH˜14 at 0° C. and extracted with DCM (2×750 nit). Organic layer was washed with water (100 mL), brine (400 mL), dried over Na₂SO₄ and concentrated under reduced pressure to yield 4-ethylamino-4-phenyl-cyclohexanone which was used in the next step without further purification. This reaction was carried out in another batch of 15.1 g scale and yield is given for 2 combined batches. Yield: 92% (17.0 g, 78.34 mmol).

Step 4: Mixture of CIS- and TRANS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (INT-1006 and INT-1007)

To a solution of 4-ethylamino-4-phenyl-cyclohexanone (17 g, 78.341 mmol, 1.0 eq.) in EtOH (250 mL) and water (200 mL) was added (NH₄)₂CO₃ (18.8 g, 195.85 mmol, 2.5 eq.) and the reaction mixture was stirred at RT for 15 min. KCN (5.09 g, 78.341 mmol, 1.0 eq.) was and the resulting mixture was stirred at 60° C. for 18 h. The reaction mixture was cooled to RT, the precipitate was filtered off, washed with water (250 mL), EtOH (300 mL), hexane (200 mL) and dried under reduced pressure to yield CIS- and TRANS-mixture 8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (13.0 g, 45.29 mmol, 58%) as a white solid. Yield: 58% (13 g, 45.296 mmol). LC-MS: m/z [M+H]⁺=288.2.

Step 5: CIS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (INT-1006)

To a solution of cis and trans mixture of 8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (12 g) in MeOH/DCM (1:1 v/v, 960 mL) was added a solution of L-tartaric acid in MeOH (25 mL). The resulting mixture was stirred at RT for 2 h and then kept in refrigerator for 16 h. The solid material was filtered off and washed with MeOH/DCM (1:5, 50 ml) to get 8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione tartrate (7.5 g) as a white solid. The solid was suspended in sat. aq. NaHCO₃ (pH˜8) and the resulting mixture was extracted with 25% MeOH-DCM (2×800 ml). Combined organic extracts were washed with water (300 nil), brine (300 ml) and dried over anhydrous Na₂SO₄. The solvent was evaporated under reduced pressure and the residue was triturated with 20% DCM-hexane to afford CIS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione as a white solid. This step was done in 2 batches (12 g & 2.4 g) and yield is given for 2 combined batches. Yield: 31.2% (5.0 g, 17.421 mmol). LC-MS: m/z [M+1]⁺=288.0.

Step 6: CIS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1008)

To a slurry of LiAlH₄ (793 mg, 20.905 mmol, 3.0 eq.) in THF (15 mL) was added a suspension of cis-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (2.0 g, 6.968 mmol, 1.0 eq.) in THF (60 mL) at 0° C. and the reaction mixture was stirred at 65° C. for 16 h. The resulting mixture was cooled to 0 (t, quenched with sat. aq. Na₂SO₄ (20 ml), stirred at RT for 1 h and filtered through celite. The celite layer was washed, with 15% MeOH-DCM (500 ml). The combined filtrate was dried over anhydrous Na₂SO₄ and concentrated, under reduced pressure. The resulting crude product was triturated with 15% DCM-Hexane to afford CIS-8-ethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1008) (1.6 g, 5.86 mmol, 84%) as a white solid. Yield: 84%(1.6 g, 5.86 mmol). LC-MS: m/z [M+H]⁺=274.2.

Synthesis of INT-1026: CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: 2-methyl-N-(1,4-dioxaspiro[4.5]decan-8-ylidene)propane-2-sulfinamide

Titanium ethoxide (58.45 g, 256.4 mmol) was added to a solution of 1,4-dioxaspiro[4.5]decan-8-one (20 g, 128.20 mmol) and 2-methylpropane-2-sulfinamide (15.51 g, 128.20 mmol) in THF (200 mL) at RT and the reaction mixture was stirred at RT for 1.8 h. The reaction mixture was cooled to 0° C. and quenched by dropwise addition of sat. aq. NaHCO₃ (500 mL) over a period of 30 min. The organic product was extracted with EtOAc (3×100 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated in vacuo to afford 10 g (crude) of 2-methyl-N-(1,4-dioxaspiro[4.5]decan-8-ylidene)propane-2-sulfinamide as a white solid (TLC system: 30% Ethyl acetate in hexane; Rf: 0.30).

Step 2: 2-methyl-N-(8-phenyl-1,4-dioxaspiro[4.5]decan-8-yl)propane-2-sulfinamide

Phenylmagnesiurn bromide (1M in THF, 116 mL, 116 mmol) was added dropwise to a solution of 2-methyl-N-(1,4-dioxaspiro[4.5]decan-8-ylidene)propane-2-sulfinamide (10 g, 38.61 mmol) in THF (500 mL) at −10° C. under argon atmosphere. The reaction mixture was stirred for 2 h at −10° C. to 0° C. The reaction completion was monitored by TLC. The reaction mixture was quenched with sat. aq. NH₄Cl (50 mL) at OT and the organic product was extracted with EtOAc (3×100 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and concentrated in vacuo. The residue was purified by column chromatography (silica gel 230-400 mesh; 40-60% ethyl acetate in hexane) to yield 6.0 g (46%) of 2-methyl-N-(8-phenyl-1,4-dioxaspiro[4.5]decan-8-yl)propane-2-sulfinamide as a liquid (TLC system: 70% Ethyl acetate in hexane; Rf: 0.30).

Step 3: 8-phenyl-1,4-dioxaspiro[4.5]decan-8-amine hydrochloride

2N solution of HCl in diethyl ether (17.80 mL, 35.60 mmol) was added to a solution of 2-methyl-N-(8-phenyl-1,4-dioxaspiro[4.5]decan-8-yl)propane-2-sulfinamide (6.0 g, 17.80 mmol) in DCM (60 mL) at 0° C. The reaction mixture was stirred at RT for 2 h. The reaction mixture was concentrated in vacuo. The residue was washed with diethyl ether to yield 3 g (crude) of 8-phenyl-1,4-dioxaspiro[4.5]decan-8-amine hydrochloride as a brown solid (TLC system: 5% MeOH in DCM; Rf: 0.10).

Step 4: 8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine

Sodium cyanoborohydride (2.17 g, 33.45 mmol) was added to a solution of 8-phenyl-1,4-dioxaspiro[4.5]decan-8-amine hydrochloride (3.0 g, 11.15 mmol) and tetrahydrofuran-3-carbaldehyde (4.46 mL, 22.30 mmol) and acetic acid (0.05 mL) in methanol (30 mL) at 0° C. The reaction mixture was stirred at RT for 16 h. The reaction mixture was concentrated in vacuo at 30° C. and to the residue sat. aq. NaHCO₃ was added. The organic product was extracted with DCM (3×30 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and solvent was concentrated under reduced pressure to get 3 g (crude) of 8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine as a semi-solid (TLC system: 10% MeOH in DCM; Rf: 0.22).

Step 5: N-methyl-8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine)

Sodium cyanoborohydride (1.76 g, 28.39 nitinol) was added to a solution of 8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine (3.0 g, 9.46 mmol), 37% formaldehyde in water (7.70 nit 94.60 mmol) and acetic acid (0.05 mL) in methanol (30 mL) at 0° C. The reaction mixture was stirred at RT for 16 h. The reaction mixture was concentrated in vacuo and to the residue sat. aq. NaHCO₃ was added. The organic product was extracted with DCM (3×30 mL). The combined organic extracts were dried over anhydrous Na₂SO₄ and solvent was concentrated under reduced pressure. The resulting residue was purified by column chromatography (silica gel 230-400 mesh; 5-6% MeOH in DCM) to yield 2.50 g (83%) of N-methyl-8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine as a semi solid (TLC system: 10% MeOH in DCM Rf: 0.25).

Step 6: 4-(methyl((tetrahydrofuran-3-yl)methyl)amino)-4-phenylcyclohexanone

5% sulfuric acid in water (25 aft) was added to N-methyl-8-phenyl-N-((tetrahydrofuran-3-yl)methyl)-1,4-dioxaspiro[4.5]decan-8-amine (2.50 g, 7.55 mmol) at 0° C. and the resulting mixture was stirred at RT for 24 h. The reaction mixture was quenched with sat. aq. NaHCO₃ and the organic product was extracted with DCM (2×50 mL). The combined organic layers were dried over anhydrous Na₂SO₄ and concentrated in vacuo to afford 2.0 g (crude) of 4-(methyl((tetrahydrofuran-3-yl)methyl)amino)-4-phenylcyclohexanone as a thick liquid (TLC system: 10% MeOH in DCM, Rf: 0.20).

Step 7: 8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione

4-(methyl((tetrahydrofuran-3-yl)methyl)amino)-4-phenylcyclohexanone (1.50 g, 5.22 mmol) was suspended in 30 mL of EtOH:H₂O (1:1 v/v) at RT under argon atmosphere. (NH₄)₂CO₃ (1.9 g, 13.05 mmol) and KCN (0.34 g, 5.22 mmol) were added. The reaction mixture was heated to 70° C. for 16 h. The reaction mixture was diluted with ice-water and the organic product was extracted with DCM (2×50 nil,). The combined organic layer was dried over anhydrous Na₂SO₄ and concentrated in vacuo to give 1.0 g (crude) of 8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione as a solid (TLC system: 70% Ethyl acetate in hexane; Rf: 0.18).

Step 8: CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione

Diastereomeric mixture of 8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (1.0 g) was separated by reverse phase preparative HPLC to afford 400 mg of isomer 1 (CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione) and 60 mg of isomer 2 (TRANS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione) and 300 mg of mixture of both isomers. Reverse phase preparative HPLC conditions: mobile phase: 10 mM ammonium bicarbonate in H₂O/acetonitrile, column: X-BRIDGE-C18 (150*30), 5 μm, gradient (T/B %): 0/35, 8/55, 8.1/98, 10/98, 10.1/35, 13/35, flow rate: 25 ml/min, diluent: mobile phase+THF.

Step 9: CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1026)

LiAlH₄ (1M in THF) (4.48 mL, 4.48 mmol) was added to a solution of CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (isomer-1) (0.4 g, 1.12 mmol) in THF:Et₂O (2:1 v/v, 15 mL) at 0° C. under argon atmosphere. The reaction mixture was stirred at 65° C. for 16 h. The mixture was cooled to 0° C., quenched with sat. aq. Na₂SO₄ (1000 mL) and filtered through celite pad. The filtrate was dried over anhydrous Na₂SO₄ and concentrated in vacuo. The residue was purified by column chromatography (silica gel 230-400 mesh; 5-6% MeOH in DCM) to yield 0.3 g (78%) of CIS-8-(methyl((tetrahydrofuran-3-yl)methyl)amino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1026) as an off white solid. (TLC system: 10% MeOH in DCM, Rf: 0.2). LC-MS: m/z [M+H]⁺=344.2.

Synthesis of INT-1031: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-3-[4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method described for INT-952 CIS-8-dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one (INT-974) was converted into CIS-1-(cyclobutyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one.

Step 2: CIS-1-(cyclobutyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-1,3-diazaspiro[4.5]decan-2-one

In analogy to the method described for INT-982 step 2 1-(cyclobutyl-methyl-8-dimethylamino-8-(3-fluorophenyl)-3-[(4-methoxyphenyl)-methyl]-1,3-diazaspiro[4.5]decan-2-one was converted into 1-(cyclobutyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-1,3-diazaspiro[4.5]decan-2-one (INT-1031).

Synthesis of INT-1037: 8-(dimethylamino)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile

Step 1: 9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one

Lithiumaluminiumhydride (2.2 equiv., 292 mmol) was suspended in THF (400 mL) and the suspension was cooled to 0° C. 8-(Dimethylamino)-8-(m-tolyl)-1,3-diazaspiro[4.5]decan-2-one (B, 75 mg, 0,261 mmol) (step 1 of INT-965) was added portionwise at 0° C. The reaction mixture was stirred 1.5 h at 0° C., then overnight at RT and then 2 h at 40° C. The reaction mixture was cooled down to 0° C., quenched carefully with sat. aq. Na₂SO₄, EtOAc (400 mL) was added and the resulting mixture was stirred for 2 h and then left without stirring for 2 h at RT. The precipitate was filtered off and washed with EtOAc and MeOH. The resulting solid residue was suspended in methanol and stirred at RT overnight. The precipitate was filtered off and disposed. The filtrate was concentrated under reduced pressure, the residue was suspended thoroughly in water (50 mL) at 40° C., the precipitate was filtered off and dried under reduced pressure to yield 9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one (11.4 g, 41%). Mass: m/z 213.2 (M+H)⁺.

Step 2: 1,3-diazaspiro[4.5]decane-2,8-dione

In analogy to the method described for INT-1003 step 3 9,12-dioxa-2,4-diazadispiro[4.2.4̂{8}.2̂{5}]tetradecan-3-one was treated with conc. aq. HCl to be converted into 1,3-diazaspiro[4.5]decane-2,8-dione. Mass: m/z 169.1 (114+H)⁺.

Step 3: 8-(dimethylamino)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (INT-1037)

In analogy to the method described for INT-965 step 1 1,3-diazaspiro[4.5]decane-2,8-dione was treated with dimethyl amine and potassium cyanide to be converted into 8-(dimethylamino)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (INT-1037). Mass: m/z. 223.2 (M±H)⁺.

To the suspension of 8-(dimethylamino)-2-oxo-1,3-diazaspiro[4.5]decane-8-carbonitrile (200 mg, 0.90 mmol) in THE (4 mL) at RT was added dropwise 1141 bromo(m-tolyl)magnesium in THE (4 equiv., 3.6 mmol, 3.6 mL) and the reaction mixture was stirred for 1 h at RT. Additional portion of 1M bromo(m-tolyl)magnesium in THF (1 equiv., 0.8 mL) was added. The reaction mixture was stirred at RT overnight, then quenched with methanol/water. Solid NH₄Cl and DCM were added to the resulting mixture and the precipitate was filtered off. The organic phase of the filtrate was separated and the aqueous phase was extracted with DCM (3×). The combined organic phases were dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel (DCM/MeOH, 100/0 to 65/35) to yield CIS-8-(dimethylamino)-8-(m-tolyl)-1,3-diazaspiro[4.5]decan-2-one (INT-1038) (81 mg, 31%). Mass: m/z 288.2 (M+H)⁺.

Synthesis of INT-1059: TRANS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: TRANS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione

To a stirred solution of 4-dimethylamino-4-phenyl-cyclohexanone (250.0 g, 1.15 mol, 1.0 eq.) in EtOH (2.5 L) and water (2.1 L) was added (NH₄)₂CO₃ (276.2 g, 2.87 mol, 2.5 eq.) and the reaction mixture was stirred at RT for 15 min. KCN (74.92 g, 1.15 mol, 1.0 eq.) was added. The reaction mixture was stirred at 60° C. for 18 h and then filtered in hot condition to get white solid which was washed with water (2.5 L), ethanol (1 L) and hexane (2.5 L), The resulting solid was dried under reduced pressure to get CIS-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (223 g, 0.776 mol, 65%) as a white solid. The filtrate was collected from multiple batches (˜450 g) which contained a mixture of cis and trans isomers. The filtrate was concentrated under reduced pressure and solid obtained was filtered and washed with water (1 L) and hexane (1 L). Solid material was dried under reduced pressure to get ˜100 g of a mixture of cis and trans (major) isomers. Crude material was partially dissolved in hot MeOH (600 mL) and cooled to RT, filtered through sintered funnel, washed with MeOH (200 mL) followed by ether (150 mL) and dried to get TRANS-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decane-2,4-dione (50 g, 0.174 mmol, ˜9-10%).

Step 2: TRANS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1059)

In analogy to the method described for INT-976 step 2 TRANS-8-dimethylamino-8-phe 3-diazaspiro[4.5]decane-2,4-dione was treated with LiAlH₄ to be converted into TRANS-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-1059). Mass: m/z 274.2 (M+H)⁺.

Synthesis of INT-1068 and INT-1069: CIS- and TRANS-8-(dimethylamino)-8-phenyl-1-(2,2,2-trifluoroethyl)-1,3-diazaspiro[4.5]decan-2-one

Step 1: 1-amino-4-dimethylamino-4-phenyl-cyclohexanecarbonitrile

To a stirred solution of 4-di -phenyl-cyclohexanone (50 g, 230,096 mmol) in MeOH (400 mL) was added NH₄Cl (24.6 g, 460.8 mmol) followed by NH₄OH (400 mL) at RT and the reaction mixture was stirred for 15 min. NaCN (22.5 g, 460.83 mmol) was added and the resulting mixture was stirred for 16 h at RT. The reaction mixture was extracted with DCM (3×750 mL). Combined organic layer was washed with water (750 mL) MLA brine (750 mL), dried over Na₂SO₄ and concentrated under reduced pressure. The residue was triturated with DCM/hexane to get crude 1-amino-4-dimethylamino-4-phenyl-cyclohexanecarbonitrile (50 g, 90%) as an off white solid which was used in next step without further purification. LC-MS: m/z [M+H]⁺=244.2 (MW calc. 244.09),

Step 2: N-(1-cyano-4-dimethylamino-4-phenyl-cyclohexyl)-2,2,2-trifluoroacetamide

To a solution of 1-amino-4-dimethylamino-4-phenyl-cyclohexanecarbonitrile (5.0 g, 20.57 mmol, 1.0 eq.) in THE (100 ml) were added DIPEA (10.72 nil, 61.71 mmol, 3.0 eq), trifluoroacetic acid (1.89 m, 24.69 mmol, 1.2 eq) and T3P (18.2 ml, 30.85 mmol, 1.5 eq) at 0° C. The reaction mixture was stirred at RT for 16 h, then diluted with water (100 ml) and extracted with 10% MeOH in DCM (2×250 mL). Combined organic layer was washed with brine (1.00 mL), dried over Na₂SO₄ and concentrated under reduced pressure to get crude N-(1-cyano-4-dimethylamino-4-phenyl-cyclohexyl)-2,2,2-trifluoroacetamide as a light yellow sticky material which was used in the next step without further purification. LC-MS: m/z [M+1]⁺=339.9 (MW calc. 339.36).

Step 3: 1-aminomethyl-N′,N′-dimethyl-4-phenyl-N-(2,2,2-trifluoroethyl)cyclohexane-1,4-diamine

To suspension of LiAlH₄ (4.03 g, 106.19 mmol, 6.0 eq.) in dry THF (40 mL) was added N-(1-cyano-4-dimethylamino-4-phenyl-cyclohexyl)-2,2,2-trifluoro-acetamide (6.0 g, 17.69 mmol, 1.0 eq.) in dry THE (100 mL) dropwise at 0° C. The reaction mixture was stirred at RT for 16 h, then quenched with sat. aq. Na₂SO₄ at 0° C., excess THF was added and the resulting mixture was stirred at RT for 2 h. The resulting suspension was filtered through celite and the filter cake was washed with 10% MeOH in DCM (150 mL). Combined filtrate was concentrated under reduced pressure to yield crude 1-aminomethyl-N′,N′-dimethyl-4-phenyl-N-(2,2,2-trifluoro-ethyl)-cyclohexane-1,4-diamine (4.2 g, crude) as a light yellow sticky material which was directly used in the next step without further purification. LC-MS: m/z [M+1]⁺=330.0 (MW calc. 329.40).

Step 4: CIS- and TRANS-8-dimethylamino-8-phenyl-1-(2,2,2-trifluoro-ethyl)-1,3-diazaspiro[4.5]decan-2-one (INT-1068 and INT-1069)

To a solution of 1-aminomethyl-N′,N′-dimethyl-4-phenyl-N-(2,2,2-trifluoro-ethyl)-cyclohexane-1,4-diamine (4.2 g, 12.76 mmol, 1.0 eq.) in toluene (60 was added KOH (4.29 g, 76.56 mmol. 6.0 eq.) in water (120 ml) at 0° C. followed by addition of COCl₂ (15.6 ml, 44.66 mmol, 3.5 eq., 20% in toluene) at 0° C. and stirred at RT for 16 h. Reaction mixture was basified with sat NaHCO₃ solution and extracted with DCM (2×200 ml). Combined organic layer was dried over Na₂SO₄ and concentrated under reduced pressure to get crude product which was purified by prep HPLC to get CIS-8-dimethylamino-8-phenyl-1-(2,2,2-trifluoro-ethyl)-1,3-diazaspiro[4,5]decan-2-one (INT-1068) (1.5 g) (major isomer, polar spot on TLC) and TRANS-8-dimethylamino-8-phenyl-1-(2,2,2-trifluoro-ethyl)-1,3-diazaspiro[4.5]decan-2-one (INT-1069) as minor isomer (non-polar spot on TLC) (120 mg, 92.93% by HPLC) as off-white solids. CIS-isomer: LC-MS: m/z [M+1]⁺=356.2 (MW calc.=355.40). HPLC: 98.53%, Column: Xbridge C-18 (100×4.6), 5μ, Diluent: MeOH, Mobile phase: A) 0.05% TFA in water; B) ACN flow rate: 1 ml/min, R_(t)=5.17 min. ¹HNMR (DMSO-d₆, 400 MHz), δ (ppm)=7.43-7.27 (m, 5H), 6.84 (s, 1H), 3.30-3.25 (m, 4H), 2.66-2.63 (d, 2H, J=12.72 Hz), 1.89 (s, 6H), 1.58-1.51 (m, 2H), 1.46-1.43 (m, 2H), 1.33-1.23 (m, 2H).

Synthesis of INT-1075: CIS-3-(8-(dimethylamino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanoic acid

A mixture of CIS-3-[8-dimethylamino-1-(1-hydroxy-cyclobutylmethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]dec-3-yl]-2,2-dimethyl-propionitrile (INT-790) (2.8 g, 6.39 mmol, 1.0 eq.) and NaOH (1.02 g, 25.57 mmol, 4.0 eq.) in ethylene glycol/water (3:1; 20 mL) was stirred at 110° C. for 36 h. The reaction mixture was acidified with aq. NaHSO₄, the precipitate was filtered off and purified by column chromatography (silica gel; 8% MeOH/DCM) to yield CIS-3-[8-dimethylamino-1-(1-hydroxy-cyclobutylmethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]dec-3-yl]-2,2-dimethyl-propionic acid (1.0 g, 2.188 mmol, 34%) as an off-white solid. LC-MS): m/z [M+1]⁺=458.0 (MW calc.=457.61).

For further intermediates the synthesis in analogy to previously described methods is given in the following table. The syntheses of the building blocks and intermediates have either been described previously within this application or can be performed in analogy to the herein described methods or by methods known to the person, skilled in the art. Such a person will also know Which building blocks and intermediates need to be chosen for synthesis of each exemplary compound.

m/z Inter- in analogy [M + mediate Chemical Name Chemical Structure to method H]⁺ INT-790 CIS-3[8-Dimethylamino-1- [(1-hydroxy-cyclobutyl)-methyl]- 2-oxo-8-phenyl-1,3-diazaspiro [4.5]decan-3-yl]-2,2-dimethyl- propionitrile

INT-897 Step 1 439.3 INT-791 CIS-3-[1-(Cyclobutyl-methyl)- 8-(ethyl-methyl-amino)-2-oxo- 8-phenyl-1,3-diazaspiro[4.5] decan-3-yl]-2,2-dimethyl- propionitrile

INT-897 Step 1 437.3 INT-792 CIS-3-[8-Dimethylamino-1- (2-methoxy-ethyl)-2-oxo-8- phenyl-1,3-diazaspiro[4.5] decan-3-yl]-2,2-dimethyl- propionitrile

INT-897 Step 1 413.3 INT-793 CIS-3-[8-Dimethylamino-1- (3-methoxy-propyl)-2-oxo-8- phenyl-1,3-diazaspiro[4.5] decan-3-yl]-2,2-dimethyl- propionitrile

INT-897 Step 1 427.3 INT-794 CIS-3-(3,4-dimethoxybenzyl)- 8-(dimethylamino)-8-phenyl- 1,3-diazaspiro[4.5]decan-2-one

INT-975 424.3 INT-796 CIS-8-Dimethylamino-3- [(4-methoxyphenyl)-methyl]- 8-(3-methoxy-propyl)-1,3- diazaspiro[4.5]decan-2-one

INT-974 390.3 INT-797 CIS-8-(Ethyl-methyl-amino)- 8-phenyl-1,3-diazaspiro[4.5] decan-2-one

INT-976 288.2 INT-894 CIS-3-[1-(Cyclobutyl-methyl)- 8-[methyl-(2-methyl-propyl)- amino]-2-oxo-8-phenyl-1,3- diazaspiro[4.5]decan-3-yl]- propionic acid; 2,2,2-trifluoro- acetic acid salt

INT-898 456.3 INT-895 CIS-3-[8-Dimethylamino-1- (2-methoxy-ethyl)-2-oxo-8- phenyl-1,3-diazaspiro[4.5] decan-3-yl]-propionic acid; 2,2,2-trifluoro-acetic acid salt

INT-898 404.2 INT-896 CIS-3-[8-Dimethylamino-1- (3-methoxy-propyl)-2-oxo-8- phenyl-1,3-diazaspiro[4.5] decan-3-yl]-propionic acid; 2,2,2-trifluoro-acetic acid salt

INT-898 418.3 INT-949 CIS-8-Dimethylamino- 1-ethyl-8-phenyl-1,3- diazaspiro[4.5]decan-2-one

INT-984 302.2 INT-950 CIS-1-(Cyclobutyl-methyl)- 8-dimethylamino-8-phenyl- 3-[phenyl-methyl]-1,3- diazaspiro[4.5]decan-2-one

INT-952 432.3 INT-954 4-Dimethylamino-4-(5- methyl-thiophen-2-yl)- cyclohexan-1-one

INT-965 238.1 INT-955 4-Dimethylamino-4- thiophen-2-yl-cyclohexan- 1-one

INT-965 224.1 INT-956 1-(1-Methyl-1H-pyrazol- 3-yl)-4-oxo-cyclohexane-1- carbonitrile

INT-958 204.1 INT-957 4-Oxo-1-pyrazin-2-yl- cyclohexane-1-carbonitrile

INT-958 202.1 INT-959 4-Dimethylamino-4-(1- methyl-1H-pyrazol-3-yl)- cyclohexan-1-one

INT-961 222.2 INT-960 4-Dimethylamino-4- pyrazin-2-yl-cyclohexan- 1-one

INT-961 220.1 INT-962 4-Dimethylamino-4- (3-methoxyphenyl)- cyclohexan-1-one

INT-965 248.2 INT-963 CIS-3-Benzyl-8- dimethylamino-8- phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-975 364.2 INT-964 4-(Ethyl-methyl- amino)-4-phenyl- cyclohexan-1-one

INT-965 232.2 INT-967 CIS-8-Dimethylamino- 8-[4-(methoxymethyloxy)- phenyl]-3-[(4-methoxy- phenyl)-methyl]-1,3- diazaspiro[4.5]decan-2-one

INT-974 454.3 INT-968 CIS-8-Dimethylamino- 8-[3-(methoxymethyloxy)- phenyl]-3-[(4-methoxy- phenyl)-methyl]-1,3- diazaspiro[4.5]decan-2-one

INT-974 454.3 INT-969 CIS-1-(Cyclobutyl- methyl)-8-dimethylamino- 8-(4-hydroxyphenyl)-3- [(4-methoxyphenyl)-methyl]- 1,3-diazaspiro[4.5]decan-2- one

INT-971 478.3 INT-970 CIS-8-Dimethylamino- 8-(4-methoxyphenyl)-3- [(4-methoxyphenyl)- methyl]-1,3-diazaspiro [4.5]decan-2-one

SC_2017 424.3 INT-972 CIS-8-Dimethylamino- 8-(3-methoxyphenyl)-3- [(4-methoxyphenyl)- methyl]-1,3-diazaspiro [4.5]decan-2-one

SC_2017 424.3 INT-973 CIS-8-Dimethylamino- 8-(4-fluorophenyl)-3-[(4- methoxyphenyl)-methyl]- 1,3-diazaspiro[4.5]decan-2- one

INT-974 412.2 INT-979 CIS-8-Dimethylamino- 1-(3-methoxy-propyl)-8- phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-984 346.2 INT-980 CIS-8-Dimethylamino- 1-(2-methoxy-ethyl)-8- phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-984 332.2 INT-981 CIS-8-Dimethylamino- 8-phenyl-1-propyl-1,3- diazaspiro[4.5]decan-2-one

INT-984 316.2 INT-983 CIS-1-(Cyclopropyl- methyl)-8-dimethylamino- 8-phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-984 328.2 INT-985 CIS-1-(Cyclobutyl-methyl)- 8-(methyl-propyl-amino)-8- phenyl-1,3-diazaspiro[4.5] decan-2-one

INT-986 370.3 INT-993 4-benzyl-4-(dimethylamino) cyclohexanone

INT-965 232.3 INT-994 CIS-8-benzyl-8- (dimethylamino)-1,3- diazaspiro[4.5]decan-2- one

INT-976 288.2 INT-995 TRANS-8-benzyl- 8-(dimethylamino)-1,3- diazaspiro[4.5]decan-2-one

INT-976 288.2 INT-997 CIS-8-((dimethylamino)- 8-(thiophen-2-yl)-1,3- diazaspiro[4.5]decan-2-one

INT-976 280.1 INT-998 TRANS-8-(dimethylamino)- 8-(thiophen-2-yl)-1,3- diazaspiro[4.5]decan-2-one

INT-976 280.1 INT-999 4-(dimethylamino)-4- (1-methyl-1H-benzo[d] imidazol-2-yl) cyclohexanone

INT-965 272.2 INT-1000 CIS-8-(dimethylamino)- 8-(1-methyl-1H-benzo[d] imidazol-2-yl)-1,3- diazaspiro[4.5]decan-2-one

INT-976 328.2 INT-1001 TRANS-8-(dimethylamino)- 8-(1-methyl-1H-benzo[d] imidazol-2-yl)-1,3-diazaspiro [4.5]decan-2-one

INT-976 328.2 INT-1009 TRANS-8-ethylamino- 8-phenyl-1,3-diaza-spiro [4.5]decan-2-one

INT-1008 274.2 INT-1013 CIS-3-(1-(cyclobutyl- methyl)-2-oxo-8-phenyl- 8-(propylamino)-1,3- diazaspiro[4.5]decan-3-yl)- 2,2-dimethylpropanenitrile

SC_5068 437.3 INT-1024 CIS-8-(dimethylamino)- 8-(3-fluorophenyl)-1,3- diazaspiro[4.5]decan-2-one

INT-977 (step 2) 292.2 INT-1025 CIS-8-(dimethylamino)-8- (4-fluorophenyl)-1,3- diazaspiro[4.5]decan-2-one

INT-974, INT-977 (step 2) 292.2 INT-1039 CIS-8-(dimethylamino)- 8-(3-(trifluoromethoxy) phenyl)-1,3-diazaspiro [4.5]decan-2-one

INT-1038 358.2 INT-1040 (CIS)-8-(dimethylamino)- 8-(3-(trifluoromethyl) phenyl)-1,3-diazaspiro[4.5] decan-2-one

INT-1038 342.2 INT-1041 (CIS)-8-(dimethylamino)- 8-(3-methoxyphenyl)-1,3- diazaspiro[4.5]decan-2-one

INT-1038 304.2 INT-1042 (CIS)-8-(5-chlorothiophen- 2-yl)-8-(dimethylamino)-1,3- diazaspiro[4.5]decan-2-one

INT-1038 314.1 INT-1043 (CIS)-8-(dimethylamino)-8- (3-fluoro-5-methylphenyl)-1,3- diazaspiro[4.5]decan-2-one

INT-1038 306.2 INT-1044 (CIS)-8-(3-chlorophenyl)- 8-(dimethylamino)-1,3- diazaspiro[4.5]decan-2-one

INT-1038 308.2 INT-1047 (CIS)-8-(methyl(oxetan- 3-ylmethyl)amino)-8- phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-1026 330.5 INT-1061 TRANS-1-(cyclopropyl- methyl)-8-dimethylamino- 8-phenyl-1,3-diazaspiro [4.5]decan-2-one

INT-984 328.2 INT-1063 CIS-1-(cyclopropylmethyl)- 8-(dimethylamino)-8-(3- fluorophenyl)-1,3-diazaspiro [4.5]decan-2-one

INT-1031 346.2 INT-1066 TRANS-1-(cyclobutylmethyl)- 8-(dimethylamino)-8-phenyl- 1,3-diazaspiro[4.5]decan-2-one

INT-987 342.3 INT-1070 CIS-8-(dimethylamino)-8- phenyl-1-(3,3,3-trifluoropropyl)- 1,3-diazaspiro[4.5]decan-2-one

INT-1068 360.2 INT-1074 CIS-8-(dimethylamino)- 8-(3-fluorophenyl)-1-((1- hydroxycyclobutyl)methyl)- 1,3-diazaspiro[4.5]decan-2-one

INT-1031 376.2

Synthesis of Exemplary Compounds Synthesis of SC_5003: CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-pyridin-4-yl)-propionamide

Into a dry tube were added successively 1 mL of a solution of CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid trifluoroacetate (INT-898) (0.1 M in DCM), 2 mL of a solution of 2-methoxypyridin-4-amine (0.2 M in DCM), 0.07 mL of triethylamine and 0.118 mL T3P (1.7 M, 50% in ethyl acetate). The reaction mixture was stirred at RT overnight, quenched with 3 ml 1M aq. Na₂CO₃ and stirred at RT for 1 h. The organic layer was separated and the aqueous layer was extracted with DCM (2×). The combined organic layers were concentrated under reduced pressure and the product was purified by HPLC to obtain CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-pyridin-4-yl)-propionamide (SC_5003). [M+H]⁺ 520.3

Synthesis of SC_5022: CIS-N-(2-cyano-pyrimidin-5-yl)-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide

CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide (SC_5002) (0.270 g, 0.631 mmol) was dissolved in 1,4 dioxane (30 mL) at RT and purged with nitrogen. To the reaction mixture were added 5-bromopyrimidine-2-carbonitrile (0.173 g, 0.946 mmol), Cs₂CO₃ (0.410 g, 1.262 mmol), Xanthphos (0.055 g, 0.095 mmol), Pd₂(dba)₃ (0.029 g, 0.032 mmol) and the resulting suspension was again purged with nitrogen for 15 minutes. The reaction mixture was stirred at 90° C. for 18 h, then cooled to RT and diluted with EtOAc (60 mL.). The insoluble solid was filtered off and the clear filtrate was concentrated under reduced pressure. The crude product was purified preparative TLC using 3% MeOH in DCM as a mobile phase to afford 52 ng (15%) of CIS-N-(2-cyano-pyrimidin-5-yl)-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide (SC_5022) as an off-white solid (TLC system: 10% MeOH in DCM; Rf: 0.56). [M+H]⁺ 532.3

Synthesis of SC_5031: CIS-3-[8-dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide

50% Propylphosphonic anhydride (T3P) solution in ethyl acetate (0.766 mL, 1.204 mmol) was added to a solution of crude CIS-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid trifluoroacetate (INT-896) (100 mg, 0.193 mmol), 2-aminoethanol (0.035 mL, 0.580 mmol) and diisopropylethylamine (0.167 mL, 0.966 mmol) in DCM (4 mL) at 0° C. The reaction mixture was warmed to RT and stirred for 4 h and then quenched with w ater. The organic product was extracted with DCM (3×20 mL). The combined organic layer was washed with sat. aq. NaHCO₃ (10 mL), brine (10 mL), dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The residue was purified by preparative HPLC to give 31 mg of CIS-3-[8-dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)propionamide (SC_5031) as an off-white solid. [M+H]⁺ 447.3

Synthesis of SC_5034: CIS-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide

30% aq. H₂O₂ (0.2 mL, 0.74 mmol) was added to a suspension of CIS-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethylpropionitrile (INT-793) (80 mg, 0.187 mmol) and K₂CO₃ (52 mg, 0.37 mmol) in DMSO at 10-15° C. The resulting reaction mixture was warmed to RT and stirred for 18 h. The reaction mixture was quenched with water and the organic product was extracted with EtOAc (3×10 mL). The combined organic layer was washed with brine, dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The resulting crude product was purified by preparative TLC (2% MeOH in DCM) to yield 30 mg of CIS-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide (SC_5034) (25%) as an off-white solid. (TLC system: 10% MeOH in DCM Rf: 0.40). [M+H]⁺ 445.3

Synthesis of SC_5055: CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide

50% Propylphosphonic anhydride (T3P) solution in DMF (1.1 mL, 1.748 mmol) was added to a mixture of crude CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionic acid (INT-899) (300 mg, 0.699 mmol, crude, contaminated with 4-methylbenzene-sulfonic acid), oxetan-3-amine hydrochloride (91 mg, 0.839 mmol) and diisopropylethylamine (0.51 mL, 2.797 mmol) in DMF (6 mL) at 0° C. The reaction mixture was warmed to RT and stirred for 6 h, then quenched with water and the organic product was extracted with EtOAc (3×20 mL). The combined organic layer was washed with sat. aq. NaHCO₃ (10 mL), brine (10 mL), dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The crude product was purified by preparative TLC by using 3% methanol in DCM as a mobile phase to yield 140 mg (41%) of CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide (SC_5055) as an off-white solid. (TLC system: 10% MeOH in DCM Rf: 0.55). [M+H]⁺ 485.3

Synthesis of SC_5056: CIS-N-(carbamoyl-ethyl)-3-[1-(cyclobutyl-methyl)-8-dimethyl-amino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide

50% propylphosphonic anhydride (T3P) solution in DMF (3.99 mL, 6.27 mmol) was added to a solution of CIS-3-[1-(cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionic acid (INT-897) (1.2 g, 2.51 moil), 2-aminoacetamide hydrochloride (0.41 g, 3.76 mmol) and diisopropylethylamine (2.63 mL, 15.06 mmol) in DMF (5 mL) at 0° C. The reaction mixture was warmed to RT and stirred for 16 h. The reaction mixture was quenched with water, the organic product was extracted with DCM (3×15 mL). The combined organic extracts were washed with brine, dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The resulting crude product was purified by reverse phase preparative HPLC to give 105 mg of CIS-N-(carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-dimethyl-amino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide (SC_5056) as an off-white solid. (TLC system: 10% MeOH in DCM R_(f): 0.4). [M+H]⁺ 442.3

Synthesis of SC_5059: CIS-3-[1-[(1-hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide

N-lodosuccinimnide (104.6 mg, 0.465 mmol) was added to a solution of CIS-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide (SC_5055) (150 mg, 0.309 mmol) in a mixture of acetonitrile and THF (1: v/v, 8 mL) al 0° C. and the resulting mixture was stirred for 16 h at RT. The reaction mixture was basified with 2N aq. NaOH to pH˜10 and the organic product was extracted with EtOAc (3×30 mL). The combined organic extracts were dried over anhydr. Na₂SO₄ and concentrated in vacuo. The resulting crude product was purified by preparative reverse phase HPLC to give 70 mg of the desired product as a formic acid salt. The isolated product was diluted with water (8 mL) and basified with solid NaHCO₃. The resulting mixture was extracted with ethyl acetate (2×30 mL), the combined organic layer was dried over anhydr. Na₂SO₄ and concentrated in vacuo to yield 60 mg (41%) of CIS-3-[1-[(1-hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide (SC_5059) as an off-white solid (TLC system: 5% MeOH in DCM; R_(f): 0.44.). [M+H]⁺ 471.3

Synthesis of SC_5063: CIS-2,2-dimethyl-3-(8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanenitrile

Step 1: CIS-3-(8-(dimethylamino)-1-(methoxymethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile

To a solution of CIS-3-(8-dimethylamino-2-oxo-8-phenyl-1,3-diaza-spiro[4.5]dec-3-yl)-2,2-dimethyl propionitrile (SC_5062) (1.8 g, 5.08 mmol, 1.0 eq.) in THF (20 ml) was added NaH (95%, 366 mg, 15.25 mmol, 3.0 eq.) at 0° C. and the reaction mixture was stirred for 20 min at RT. A solution of methoxymethyl chloride (0.57 ml, 7.62 mmol, 1.5 eq.) in THF (5 ml) was added at 0° C. and the resulting mixture was stirred at RT for 16 h. The reaction mixture was diluted with water (20 ml) and extracted with EtOAc (2×50 ml). The combined organic layers were washed with water (50 ml) and brine (50 ml), dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The resulting crude product was purified by column chromatography (neutral alumina; 0.2% MeOH/DCM) to yield CIS-3-(8-(dimethylamino)-1-(methoxymethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (700 ng, 1.75 mmol, 34%) as an off-white sticky solid. LC-MS: m/z [M+H]⁺=399.3 (MW calc.=398.54).

Step 2: CIS-3-(1-(methoxymethyl)-8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile

To a solution of CIS-3-(8-(dimethylamino)-1-(methoxymethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (700 mg, 1.75 mmol, 1.0 eq.) in acetonitrile (20 ml) and THF (10 ml) was added N-iodosuccinimide (590 mg, 2.63 mmol, 1.5 eq.) at 0° C. and the mixture was stirred at RT for 3 h. The reaction mixture was diluted with water (20 ml) and 1N aq. NaOH (5 ml) and extracted with DCM (2×30 ml). The combined organic layers were washed with brine (40 ml), dried over anhydr. Na₂SO₄ and concentrated under reduced pressure to give CIS-3-(1-(methoxymethyl)-8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (350 mg, 0.911 mmol, 52%) which was used directly for next step without further purification. LC-MS: m/z [M+H]+=385.2 (MW calc.=384.52).

Step 3: CIS-2,2-dimethyl-3-(8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanenitrile (SC_5063)

To a solution of CIS-3-(1-(methoxymethyl)-8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (400 mg, 1.04 mmol, 1.0 eq.) in MeOH (10 ml) was added 2M aq. HCl (30 mil) at 0° C. and the mixture was stirred at RT for 16 h. The reaction mixture was basified with 2M aq. NaOH and extracted with DCM (2×25 ml). The combined organic layers were washed with brine (30 ml), dried over anhydr. Na₂SO₄ and concentrated under reduced pressure to give CIS-2,2-dimethyl-3-(8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanenitrile (SC_5063) (300 mg, 0.882 mmol, 84%) which was 95.72% pure according to HPLC. LC-MS: m/z [M+H]+=341.27 (MW calc.=340.46). ¹H-NMR (DMSO-d6, 400 MHz), δ (ppm)=7.42-7.19 (m, 5H), 6.78 (bs, 1H), 3.36 (s, 2H), 3.18 (s, 2H), 1.96-1.85 (m, 7H), 1.66 (bs, 2H), 1.46-1.43 (nm, 2H), 1.25 (s, 6H).

Synthesis of SC_5074: CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide

Step 1: CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile

To a solution of CIS-3-(8-(ethyl(methyl)amino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (SC_5061) (250 mg, 0.679 mmol, 1.0 eq.) in DMSO (10 ml) was added NaOH (108 mg, 2.716 mmol, 4.0 eq.) at RT and the reaction mixture was stirred at 60° C. for 30 min. A solution of 1-oxa-spiro[2.3]hexane (142 mg, 1.69 mmol, 2.5 eq.) in DMSO (1 ml) was added at RT. The reaction mixture was stirred at 55° C. for 161, then diluted with water (100 ml) and extracted with ethyl acetate (60 ml). The organic layer was washed with water (50 ml) and brine (50 ml), dried over anhydr Na₂SO₄ and concentrated under reduced pressure. The resulting crude product was purified by column chromatography (neutral alumina; 30% ethyl acetate/hexane) to yield CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (120 mg, 0.265 mmol, 39%) as an off-white solid. LC-MS: m/z [M+H]+=453.1 (MW calc. 452.63).

Step 2: CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide (SC_5074)

In analogy to the method described for SC_5034 CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile was treated with 30% aq. H₂O₂ in the presence of DMSO and potassium carbonate to be converted into CIS-3-(8-(ethyl(methyl)amino)-1-((1-hydroxycyclobutyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide (SC_5074). Yield: 44% (55 mg, 0.117 mmol). LC-MS: m/z [M+H]+=471.1 (MW calc.=470.65). ¹HNMR (DMSO-d6, 400 MHz), δ (ppm)=7.34-722 (m, 5H), 7.16 (s, 1H), 6.95 (s, 1H), 6.11 (s, 1H), 3.25 (s, 2H), 3.16 (s, 2H), 3.09 (s, 2H), 2.68-2.65 (m, 2H), 2.20-1.99 (m, 6H), 1.95-1.87 (m, 5H), 1.63-1.61 (m, 1H), 1.43-1.23 (m, 6H), 1.02 (s, 6H), 0.99 (t, 3H, J=6.94 Hz).

Synthesis of SC_5075: CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile

CIS-1-(cyclopropylmethyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-984) (50 mg, 0.15 mmol) was added to a suspension of NaH (60% in mineral oil, 18 mg, 0.45 mmol) in DMF (5 mL) at 0° C. and the reaction mixture was stirred at RT for 5 min. 2-Cyano-2-methylpropyl 4-methylbenzenesulfonate (113 rag, 0.45 mmol) was added at 0° C. and stirring was continued 120° C. for 16 h. The reaction mixture was quenched with cold water and the organic product was extracted with DCM (3×20 mL). The combined organic extracts were dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The above described reaction was repealed with 300 mg of CIS-1-(cyclopropylmethyl)-8-(dimethylamino)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (INT-984). Both reaction batches were combined and purified by column chromatography (silica gel 100-200 mesh, 0-10% MeOH in DCM) to yield the product which was further purified by reverse phase preparative HPLC to afford 41 mg (16%) of CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanenitrile (SC_5075) as an off-white solid. (TLC system: 10% MeOH in DCM; Rf: 0.40). ¹H NMR (DMSO-d6): δ 7.37-7.23 (m, 5H), 3.38 (s, 2H), 3.22 (s, 2H), 2.94 (d, 2H), 2.71-2.68 (m, 2H), 2.18 (t, 2H), 1.97 (s, 6H), 1.42-1.30 (m, 4H), 1.26 (s, 6H), 0.93-0.92 (m, 1H), 0.48-0.44 (m, 2H), 0.28-0.24 (m, 2H). [M+H]⁺ 471.3

Synthesis of SC_5079: CIS-8-(dimethylamino)-3-(3-(1,1-dioxidothiomorpholino)-2,2-dimethyl-3-oxopropyl)-1-((1-hydroxycyclobutyl)methyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

Step 1: CIS-3-(2,2-dimethyl-3-oxo-3-thiomorpholinopropyl)-8-(dimethylamino)-1-((1-hydroxycyclobutyl)methyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one

To a solution of CIS-3-[8-dimethylamino-1-(1-hydroxy-cyclobutylmethyl)-2-oxo-8-phenyl-1,3-diaza-spiro[4.5]dec-3-yl]-2,2-dimethyl-propionic acid (INT-1075) (250 mg, 0.55 mmol, 1.0 eq) in DCM (20 mL) were added DIPEA (0.29 mL, 1.65 mmol, 3.0 eq.), HATU (209 mg, 0.55 mmol, 1.0 eq.) and thiomorpholine (83 μL, 0.82 mmol, 1.5 eq.) at 0° C. The reaction mixture was stirred at RT for 16 h, diluted with DCM (100 mL), washed with water (50 mL), sat. aq. NaHCO₃ (50 mL) and brine (50 mL). Organic layer was dried over sodium sulfate and concentrated under reduced pressure to get crude product which was purified by column chromatography (silica gel; 3% MeOH in DCM) to yield CIS-8-dimethylamino-3-(2,2-dimethyl-3-oxo-3-thiomorpholin-4-yl-propyl)-1-(1-hydroxy-cyclobutylmethyl)-8-phenyl-1,3-diaza-spiro[4.5]decan-2-one (220 mg, 0.40 mmol, 73%) as an off-white solid. LC-MS: m/z [M+1]=543.3 (MW calc.=542.78).

Step 2: CIS-8-(dimethylamino)-3-(3-(1,1-dioxidothiomorpholino)-2,2-dimethyl-3-oxopropyl)-1-((1-hydroxycyclobutyl)methyl)-8-phenyl-1,3-diazaspiro[4.5]decan-2-one (SC_5079)

To a solution of CIS-8-dimethylamino-3-(2,2-dimethyl-3-oxo-3-thiomorpholin-4-yl-propyl)-1-(1-hydroxy-cyclobutylmethyl)-8-phenyl-1,3-diaza-spiro[4.5]decan-2-one (270 mg, 0.5 mmol, 1.0 eq) in acetone/THF/H₂O (40 mL, 6/1/1 v/v/v) was added oxone (615 mg, 1.0 mmol, 2.0 eq.) at 0° C. The reaction mixture was stirred at RT for 16 h, quenched with sat. aq. Na₂SO₃, diluted with EtOAc (150 mL) and washed with sat. aq. NaHCO₃ (75 mL). Organic layer was dried over sodium sulfate and concentrated under reduced pressure to get crude product which was purified by column chromatography (silica gel; 4% MeOH in DCM) to yield CIS-8-dimethylamino-3-[3-(1,1-dioxo-116-thiomorpholin-4-yl)-2,2-dimethyl-3-oxo-propyl]-1-(1-hydroxy-cyclobutylmethyl)-8-phenyl-1,3-diaza-spiro[4.5]decan-2-one (SC_5079) (100 mg, 0.17 mmol, 34%) as a white solid. ¹HNMR (DMSO-d₆ 400 MHz), δ (ppm)=7.37-7.25 (m, 5H), 5.91 (s, 1H), 3.92 (bs, 4H), 3.28 (bs, 4H), 3.13 (bs, 4H), 3.07 (s, 2H), 2.64 (d, 2H, J=13.44 Hz), 2.07-2.00 (m, 4H), 1.96 (s, 6H), 1.87-1.85 (m, 2H), 1.61-1.64 (m, 1H), 1.40-1.30 (m, 5H), 1.19 (s, 6H). LC-MS: m/z [M+1]⁺=575.1 (MW calc.=574.78).

Synthesis of SC_5083: CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl)-N,N-dimethylpropanamide

Step 1: sodium CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl)propanoate

To a solution of CIS-1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-1,3-diazaspiro[4.5]decan-2-one (INT-1063) (100 mg, 0.29 mmol) in dry THF (2.4 L) cooled to 0° C. was added potassium tert-butoxide (1.5 equiv., 0.43 mmol, 49 mg). The reaction mixture was stirred for 15 min at 0° C. and methyl 3-bromopropionate (1.2 equiv., 0.35 mmol, 38 μL) was added dropwise. The reaction mixture was stirred at RT for 16 h and new portions of methyl 3-bromopropionate (1.2 equiv., 0.35 mmol, 38 μL) and potassium tert-butoxide (1.5 equiv., 0.43 mmol, 49 mg) were added. The reaction mixture was stirred for 3 h at RT, quenched with sat. aq. NaHCO₃ and then extracted with DCM (2×). To the combined organic phase 2 mL of 2M aq. NaOH were added, the resulting mixture was vigorously stirred overnight at RT and then concentrated under reduced pressure to yield crude sodium CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl)propanoate (60 mg, 50%) which was used in the next step without further purification. LC-MS: m/z [M+1]+=418.3 (MW calc. 417.3)

Step 2: CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl)-N,N-dimethylpropanamide (SC_5083)

To a solution of sodium CIS-3-[1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl]propanoate (60 mg, 0.144 mmol, 60 mg) and N-methylmethanamine (8 equiv., 1.15 mmol, 2 M in THF, 0.57 mL) in DCM (1 mL) was added propylphosphonic anhydride solution ≧50 wt. % in EtOAc (2 equiv., 0.29 mmol, 0.17 mL). The reaction mixture was stirred at RT overnight, then quenched with sat. aq. NaHCO₃ (2 mL) and diluted with EtOAc. The organic phase was separated and the aqueous phase extracted with EtOAc. The combined organic layers were dried over anhydr. Na₂SO₄ and concentrated under reduced pressure. The resulting crude product was purified by flash chromatography (eluent gradient DCM/MeOH) to yield CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl)-N,N-dimethylpropanamide (SC_5083) (25 mg, 39%). LC-MS: m/z [M+H]⁺=445.3 (MW calc.=444.29). ¹H NMR (600 MHz, DMSO) δ 7.40 (td, 1H), 7.21-7.05 (nm, 3H), 3.27 (t, 21H), 3.18 (s, 2H), 2.95 (s, 3H), 2.91 (d, 2H), 2.79 (s, 3H), 2.67-2.55 (m, 2H), 2.47 (t, 2H), 2.13 (ddd, 2H), 1.99 (s, 6H), 1.43-1.21 (m, 4H), 0.92 (ddt, 1H), 0.49-0.41 (m, 2H), 0.30-0.21 (m, 2H).

For further exemplary compounds the last synthesis step in analogy to previously described methods is given in the following table. The syntheses of the building blocks and intermediates have either been described previously within this application or can be performed in analogy to the herein described methods or by methods known to the person, skilled in the art. Such a person will also know which building blocks and intermediates need to be chosen for synthesis of each exemplary compound.

in analogy m/z Example Chemical Name Reactant I Reactant II to method [M + H]⁺ SC_5001 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 pyridazin-3-amine SC_5055 507.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide SC_5002 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 NH₄Cl SC_5055 429.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide SC_5004 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 6-methoxypyridin-3- SC_5003 520.3 diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyridin-3-yl)-propionamide amine SC_5005 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 3-methoxypyridin-4- SC_5003 520.3 diazaspiro[4.5]decan-3-yl]-N-(3-methoxy-pyridin-4-yl)-propionamide amine SC_5006 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 6-methoxypyridazin-3- SC_5003 521.3 diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyridazin-3-yl)-propionamide amine SC_5007 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 5-(methylsulfo- SC_5003 568.3 diazaspiro[4.5]decan-3-yl]-N-(5-methylsulfonyl-pyridin-2-yl)- nyl)pyridin-2-amine propionamide SC_5008 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 5-methoxypyridin- SC_5003 520.3 diazaspiro[4.5]decan-3-yl]-N-(5-methoxy-pyridin-2-yl)-propionamide 2-amine SC_5009 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 6-(methylsulfo- SC_5003 568.3 diazaspiro[4.5]decan-3-yl]-N-(6-methylsulfonyl-pyridin-3-yl)- nyl)pyridin-3-amine propionamide SC_5010 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 6-methoxypyrazin- SC_5003 521.3 diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyrazin-2-yl)-propionamide 2-amine SC_5011 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 4-methoxypyridin- SC_5003 520.3 diazaspiro[4.5]decan-3-yl]-N-(4-methoxy-pyridin-2-yl)-propionamide 2-amine SC_5012 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 oxazol-5-ylmethanamine SC_5003 494.3 diazaspiro[4.5]decan-3-yl]-N-(oxazol-5-yl-methyl)-propionamide SC_5013 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 oxazol-2-ylmethanamine SC_5003 494.3 diazaspiro[4.5]decan-3-yl]-N-(oxazol-2-yl-methyl)-propionamide SC_5014 CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-piperidin-1-yl]-3-oxo- INT 998 piperidine-3,4-diol SC_5003 513.3 propyl]-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5015 CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo- INT 998 pyrrolidine-3,4-diol SC_5003 499.3 propyl]-8-dimethylamiao-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5016 CIS-1-(Cyclobutyl-methyl)-3-[(3S,4R)-3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo- INT 998 (3S,4R)-pyrrolidine- SC_5003 499.3 propyl]-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one 3,4-diol SC_5017 CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3[3-(3-hydroxy-piperidin- INT 998 piperidin-3-ol SC_5003 497.3 1-yl)-3-oxo-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5018 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 1-(aminomethyl)cyclo- SC_5003 497.3 diazaspiro[4.5]decan-3-yl]-N-[(1-hydroxy-cyclobutyl)-methyl]-propionamide butanol SC_5019 CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3-[3-oxo-3-(5,6,7,8-tetrahydro- INT 998 5,6,7,8-tetrahydro- SC_5003 520.3 [1,2,4]triazolo[1,5-a]pyrazin-7-yl)-propyl]-8-phenyl-1,3- [1,2,4]triazolo[1,5- diazaspiro[4.5]decan-2-one a]pyrdzine SC_5020 CIS-3-[3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 998 3-amino-N,N- SC_5003 512.4 diazaspiro[4.5]decan-3-yl]-propanoylamino]-N,N-dimethyl-propionamide dimethylpropanamide SC_5023 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- SC_5002 2-bromopyrimidine SC_5022 507.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyrimidin-2-yl-propionamide SC_5024 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT-899 2-aminopyrimidin- SC_5055 523.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(4-hydroxy-pyrimidin-2-yl)- 4(3H)-one propionamide SC_5025 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- SC_5002 2-bromo-4- SC_5022 537.3 phenyl-1,3-diazaspiro[4,5]decan-3-yl]-N-(4-methoxy-pyrimidin-2-yl)- methoxypyrimidine propionamide SC_5026 CIS-3-[1-(Cyclobutyl-methyl)-8-methylamino-2-oxo-8-phenyl-1,3- SC_5046 — SC_5059 427.3 diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5027 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8- SC_5054 — SC_5059 459.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide SC_5028 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8- SC_5002 — SC_5059 415.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide SC_5029 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8- SC_5052 — SC_5059 429.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5030 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8- SC_5001 — SC_5059 493.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide SC_5032 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3- INT 896 methylamine SC_5031 417.3 diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5033 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3- INT 896 pyrimidin-5- SC_5031 481.3 diazaspiro[4.5]decan-3-yl]-N-pyrimidin-5-yl-propionamide amine SC_5035 CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3- INT-792 — SC_5034 431.3 diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5036 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl- INT 899 pyridin-3-amine SC_5055 506.3 1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-3-yl-propionamide SC_5037 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl- INT 899 pyridin-4-amine SC_5055 506.3 1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-4-yl-propionamide SC_5038 CIS-2-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- INT 896 2-amino-2- SC_5031 502.3 diazaspiro[4.5]decan-3-yl]-propanoylamino]-2-methyl-propionamide methylpropanamide SC_5039 CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- INT 896 2-(methylsulfo- SC_5031 523.3 diazaspiro[4.5]decan-3-yl]-N-(2-methylsulfonyl-ethyl)-propionamide nyl)ethanamine SC_5040 CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- INT 896 2-aminoethanol SC_5031 461.3 diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide SC_5041 CIS-8-Dimethylamino-1-(3-methoxy-propyl)-3-[3-oxo-3-(3-oxo- INT 896 piperazin-2-one SC_5031 500.3 piperazin-1-yl)-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one SC_5042 CIS-(2R)-1-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3- INT 896 (R)-pyrrolidine-2- SC_5031 514.3 diazaspiro[4.5]decan-3-yl]-propanoyl]-pyrrolidine-2-carboxylic acid amide carboxamide SC_5043 CIS-N-(Carbamoyl-methyl)-3-[8-dimethylamino-1-(3-methoxy-propyl)-2- INT 896 2-aminoacetamide SC_5031 474.3 oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide SC_5044 CIS-3-[8-Dimethylamino-1-[(l-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl- INT 899 pyridin-2-amine SC_5055 506.3 1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-2-yl-propionamide SC_5045 CIS-3-[1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-2-oxo-8-phenyl-1,3- INT-791 — SC_5034 455.3 diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5046 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT-897 — SC_5034 441.3 diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide product step 1 SC_5047 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT-898 NH₄Cl SC_5031 413.3 diazaspiro[4.5]decan-3-yl]-propionamide SC_5048 CIS-3-[1-(Cyclobutyl-methyl)-8-[methyl-(2-methyl-propyl)-amino]-2-oxo-8- INT 894 methylamine SC_5031 469.4 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5049 CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3- INT 898 methylamine SC_5031 427.3 diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide SC_5051 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 pyrimidin-5- SC_5055 507.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyrimidin-5-yl-propionamide amine SC_5052 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 methylamine SC_5055 443.3 phenyl-1,3-diazaspiro [4.5]decan-3-yl]-N-methyl-propionamide SC_5053 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 2-methoxy- SC_5055 487.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-ethyl)-propionamide ethanamine SC_5054 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8- INT 899 2-aminoethanol SC_5055 473.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide SC_5057 CIS-N-(Carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-methylamino-2- SC_5056 — SC_5059 484.3 oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5058 CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl- INT-790 — SC_5034 457.3 1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide SC_5060 CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8- SC_5058 — SC_5059 443.3 phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide

in analogy Example Chemical name Reactant I Reactant II to method ¹H NMR data m/z (M + H)⁺ SC_5061* CIS-3-[8-(Ethyl-methyl-amino)-2- INT-797 3-bromo-2,2- step 1 of INT- 1HNMR (DMSO-d6, 400 MHz, at 100° C.), δ (ppm) = 7.34-7.21 369.2 oxo-8-phenyl-1,3- dimethyl- 897 (m, 5H), 6.70 (bs, 1H), 3.28 (s, 2H), 3.19 (s, 2H), 2.32-2.24 (m, diazaspiro[4.5]decan-3-yl]-2,2- propionitrile 4H), 2.06 (s, 3H), 1.87-1.82 (m, 4H), 1.45-1.37 (bs, 2H), 1.27 (s, dimethyl-propionitrile 6H), 0.93 (t, 3H, 6.8 Hz). SC_5062* CIS-3-(8-Dimethylamino-2-oxo-8- INT-976 3-bromo-2,2- step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.35-7.24 (m, 5H), 355.2 phenyl-1,3-diazaspiro[4.5]decan-3- dimethyl- 897 7.03 (bs, 1H), 3.25 (s, 2H), 3.15 (s, 2H), 2.32 (bs, 2H), 1.92 (s, yl)-2,2-dimethyl-propionitrile propionitrile 6H), 1.82 (bs, 4H), 1.38 (bs, 2H), 1.24 (s, 6H). SC_5064 CIS-3-[8-(Ethyl-methyl-amino)-2- SC_5061 SC_5034 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.33-7.22 (m, 5H), 387.5 oxo-8-phenyl-1,3- 7.14 (bs, 1H), 6.83-6.79 (m, 2H), 3.07 (s, 2H), 3.01 (s, 2H), 2.32 diazaspiro[4.5]decan-3-yl]-2,2- (bs, 2H), 2.11 (bs, 2H), 1.96 (s, 3H), 1.78-1.69 (m, 4H), 1.31 (bs, dimethyl-propionamide 2H), 0.99 (s, 6H), 0.90 (t, 3H, J = 6.66 Hz). SC_5065* CIS-3-[8-(Ethyl-methyl-amino)-1- SC_5061 methyl iodide step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.34-722 (m, 5H), 383.2 methyl-2-oxo-8-phenyl-1,3- 953 3.38 (s, 2H), 3.21 (s, 2H), 2.71-2.64 (m, 5H), 2.19-2.16 (m, 4H), diazaspiro[4.5]decan-3-yl]-2,2- 1.96 (s, 3H), 1.37-1.30 (m, 4H), 1.25 (s, 6H), 0.98 (t, 3H, J = dimethyl-propionitrile 6.48 Hz). SC_5066 CIS-3-[8-(Ethyl-methyl-amino)-1- SC_5065 SC_5034 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.34-723 (m, 5H), 401.2 methyl-2-oxo-8-phenyl-1,3- 7.15 (s, 1H), 6.90 (s, 1H), 3.13 (s, 4H), 2.67-2.60 (m, 5H), 2.12- diazaspiro[4.5]decan-3-yl]-2,2- 2.09 (m, 4H), 1.95 (s, 3H), 1.33-1.25 (m, 4H), 1.01-0.97 (m, 9H). dimethyl-propionamide SC_5067 CIS-2,2-Dimethyl-3-(8- SC_5063 SC_5034 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.42 (d, 2H, J = 8), 358.48 methylamino-2-oxo-8-phenyl-1,3- 7.33-7.29 (t, 2H, J = 8), 7.19-7,15 (m, 2H), 6.90 (s, 1H), 6.51 (bs, diazaspiro[4.5]decan-3-yl)- 1H), 3.12-3.09 (m, 4H), 1.90-1.83 (m, 7H), 1.74-1.69 (m, propionamide 2H), 1.41-1.38 (d, 2H, J = 12 ), 1.01 (s, 6H) SC_5068* CIS-3-(8-Ethylamino-2-oxo-8- INT-1008 3-bromo-2,2- step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.42 (d, 12H, J = 355.1 phenyl-1,3-diazaspiro[4.5]decan-3- dimethyl-propionitrile 897 7.32 Hz), 7.30 (t, 2H, J = 7.20 Hz), 7.17 (t, 1H, J = 7.12 Hz), yl)-2,2-dimethyl-propionitrile 6.78 (s, 1H), 3.35 (s, 2H), 3.17 (s, 2H), 2.05 (m, 7H), 1.67-1.43 (m, 4H), 1.25 (s, 6H), 0.91 (t, 3H, J = 6.78 Hz). SC_5069 CIS-3-(8-Ethylamino-2-oxo-8- SC_5068 SC_5034 1HNMR (DMSO-d6, 400 MHz, at 100° C.), δ (ppm) = 7.45 (d, 373.0 phenyl-1,3-diazaspiro[4.5]decan-3- 2H, J = 6.52 Hz), 7.32 (t, 2H, J = 7.2 Hz), 7.21 (t, 1H, J = 6.66 yl)-2,2-dimethyl-propionamide Hz), 6.64 (bs, 2H), 6.18 (s, 1H), 3.16 (s, 4H), 2.19 (bs, 2H), 1.91- 1.79 (m, 6H), 1.44 (bs, 2H), 1.07 (s, 6H), 0.95 (t, 3H, J = 6.62 Hz). SC_5070 CIS-3-(8-Dimethylamino-2-oxo-8- SC_5062 SC_5034 1H NMR (600 MHz, DMSO) δ 7.39-7.29 (m, 4H), 7.29-7.22 373.3 phenyl-1,3-diazaspiro[4.5]decan-3- (m, 1H), 7.14 (s, 1H), 6.81 (s, 1H), 6.76 (s, 1H), 3.09 (s, 2H), yl)-2,2-dimethyl-propionamide 3.03 (s, 2H), 2.40-2.21 (m, 2H), 1.93 (s, 6H), 1.82-1.74 (m, 2H), 1.74-1.61 (m, 2H), 1.37-1.29 (m, 2H), 1.01 (s, 6H). SC_5071 CIS-3-[1-(Cyclobutyl-methyl)-8- SC_5068 cyclobutylmethylbromide step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.42 (d, 2H, J = 7.48 441.0 ethylamino-2-oxo-8-phenyl-1,3- 953 (for step Hz), 7.30 (t, 2H, J = 7.32 Hz), 7.19-7.14 (m, 2H), 6.94 (s, 1H), diazaspiro[4.5]decan-3-yl]-2,2- 1), SC_5034 3.12 (s, 4H), 3.05 (d, 2H, J = 7.08 Hz), 2.14-2.03 (m, 4H), 1.95- dimethyl-propionamide (for step 2) 1.88 (m, 4H), 1.79-1.66 (m, 4H), 1.53-1.25 (m, 4H), 1.01 (s, 6H), 0.95 (t, 3H). SC_5072 CIS-3-[8-Dimethylamino-1-(oxetan- SC_5062 toluene-4- step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.37-7.24 (m, 5H), 443.3 3-yl-methyl)-2-oxo-8-phenyl-1,3- sulfonic acid 953 (for step 7.14 (s, 1H), 6.92 (s, 1H), 4.62-4.58 (m, 2H), 4.35 (t, 2H, J = diazaspiro[4.5]decan-3-yl]-2,2- oxetan-3-ylmethyl ester 1), SC_5034 6.02 Hz), 3.29 (d, 2H, J = 7.28 Hz), 3.14-3.08 (m, 5H), 2.68-2.65 dimethyl-propionamide (for step 2) (m, 2H), 2.01-1.95 (m, 8H), 1.33-1.22 (m, 4H), 1.00 (s, 6H). SC_5073 CIS-3-[1-(Cyclopropyl-methyl)-8- SC_5075 SC_5034 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.35-7.25 (m, 5H), 427.4 dimethylamino-2-oxo-8-phenyl-1,3- 7.15 (s, 1H), 6.90 (s, 1H), 3.13 (s, 4H), 2.90 (d, 2H, J = 6.32 Hz), diazaspiro[4.5]decan-3-yl]-2,2- 2.68-2.65 (m, 2H), 2.15-2.09 (m 2H), 1.98 (s, 6H), 1.36-1.23 (m, dimethyl-propionamide 4H), 1.01(s, 6H), 0.91 (m, 1H), 0.44 (d, 2H, J = 6.84 Hz), 0.24 (d, 2H, J = 4.08 Hz). SC_5076 CIS-8-Dimethylatnino-3-(2,2- INT-1075 morpholine SC_5031 527.5 dimethyl-3-morpholin-4-yl-3-oxo- propyl)-1-[(1-hydroxy-cyclobutyl)- methyl]-8-phenyl-1,3- diazaspiro[4.5]decan-2-one SC_5077 CIS-3-[8-Dimethylamino-1-[(1- INT-1075 2-aminoethanol SC_5031 1HNMR (DMSO-d6, 400 MHz at 100° C.), δ (ppm) = 7.33-7.18 501.2 hydroxy-cyclobutyl)-methyl]-2-oxo- (m, 6H), 5.66 (bs, 1H), 4.19 (bs, 1H), 3.40 (bs, 2H), 3.25-3.22 8-phenyl-1,3-diazaspiro[4.5]decan- (m, 4H), 3.13 (bs, 4H), 2.62-2.59 (m, 2H), 2.10-2.05 (m, 9H), 3-yl]-N-(2-hydroxy-ethyl)-2,2- 1.91-1.89 (m, 2H), 1.70-1.66 (m, 2H), 1.41-1.28 (m, 4H), 1.09 (s, dimethyl-propionamide 6H). SC_5078 CIS-3-[1-[(1-Cyano-cyclobutyl)- SC_5062 toluene-4- step 1 of INT- ¹HNMR (DMSO-d₆, 400 MHz), δ (ppm) = 7.37-7.31 (m, 4H), 466.2 methyl]-8-dimethylamino-2-oxo-8- sulfonic acid 1- 953 (for step 7.27-7.23 (m, 1H ), 7.14 (s, 1H), 6.93 (s, 1H), 3.32 (s, 2H), 3.17 phenyl-1,3-diazaspiro[4.5]decan-3- cyano- 1), SC_5034 (s, 4 H), 2.69-2.65 (d, 2H), 2.45-2.38 (m, 2H), 2.35-2.28 (m, yl]-2,2-dimethyl-propionamide cyclobutylmethyl ester (for step 2) 2H), 2.0-1.95 (m, 10H), 1.41-1.38 (d, 2H), 1.30-1.23 (t, 2H), 1.02 (s, 6H). SC_5080* TRANS-3-[1-(Cyclopropyl-methyl)- INT-1059 3-bromo-2,2- step 1 of INT- 1HNMR at 20° C. (DMSO-d6, 400 MHz), δ (ppm) = 7.44-7.28 409.2 8-dimethylamino-2-oxo-8-phenyl- dimethyl- 897 (for step (m, 5H), 3.46 (s, 2H), 3.23 (s, 2H), 2.72-2.66 (m, 2H), 2.57-2.55 1,3-diazaspiro[4.5]decan-3-yl]-2,2- propionitrile 1), step 1 of (m, 2H), 1.91 (s, 6H), 1.55-1.45 (m, 6H), 1.27 (s, 6H), 0.51 (bs, dimethyl-propionitrile (step 1), INT-953 (for 1H), 0.19-0.14 (m, 2H), (−0.22)-(−0.26) (m, 2H). cyclopropylmethylbromide step 2) (step 2) SC_5081 TRANS-3-[8-Dimethylamino-1-[(1- INT-1059 3-bromo-2,2-dimethyl- step 1 of INT- 1HNMR (DMSO-d6, 400 MHz), δ (ppm) = 7.43-7.27 (m, 5H), 457.2 hydroxy-cyclobutyl)-methyl]-2-oxo- propionitrile 897 (for step 7.21 (bs, 1H), 7.05 (bs, 1H), 5.75 (s, 1H), 3.17 (s, 2H), 2.67-2.65 8-phenyl-1,3-diazaspiro[4.5]decan- (step 1), 1- 1), SC_5074 (bs, 2H), 2.55 (s, 2H), 1.91 (s, 6H), 1.73-1.68 (m, 4H), 1.48-1.34 3-yl]-2,2-dimethyl-propionamide oxaspiro[2.3]hexane (for steps 2 and (m, 7H), 1.04 (s, 6H), 0.90-0.83 (m, 1H). (step 2) 3) SC_5082 TRANS-3-(8-Dimethylamino-2-oxo- INT-1061 3-bromo-2,2- step 1 of INT- 1HNMR at 100° C. (DMSO-d6, 400 MHz), δ (ppm) = 7.37-7.25 373.3 8-phenyl-1,3-diazaspiro[4.5]decan- dimethyl- 897 (for step (m, 5H), 6.68 (bs, 2H), 6.30 (bs, 1H), 3.22 (s, 2H), 3.17 (s, 2H), 3-yl)-2,2-dimethyl-propionamide propionitrile 1), SC_5034 2.16 (bs, 2H), 1.99 (bs, 8H), 1.70-1.68 (m, 2H), 1.43-1.38 (m, (step 1) (for step 2) 2H), 1.09 (s, 6H). SC_5084 CIS-3-[1-(Cyclopropyl-methyl)-8- INT-1031 2-cyano-2- SC_5075 (step 1H NMR (DMSO-d6): δ 7.41-7.36 (m, 1H), 7.18-7.07 (m, 4H), 445.3 dimethylamino-8-(3-fluorophenyl)-2-oxo-1,3- methylpropyl 4- 1), SC_5034 6.89 (br, s, 1H), 3.14 (s, 4H), 2.90 (d, 2H), 2.64 (d, 2H), 2.11 (t, diazaspiro[4.5]decan-3- methylbenzenesulfonate (step 2) 2H), 1.98 (s, 6H), 1.34 (d, 2H), 1.27 (t, 2H), 1.02 (s, 6H), 0.93- yl]-2,2-dimethyl-propionamide (step 1) 0.88 (m, 1H), 0.47-0.42 (m, 2H), 0.26-0.22 (m, 2H). SC_5085 CIS-1-((1-(cyclopropylmethyl)-8- INT-983 (1- step 1 of INT- 425.3 (dimethylamino)-2-oxo-8-phenyl- cyanocyclopropyl)methyl 4- 897 (for step 1,3-diazaspiro[4.5]decan-3- methylbenzenesulfonate 1), SC_5034 yl)methyl)cyclopropanecarboxamide (step 1) (for step 2) SC_5086 CIS-3-((1-(cyclopropylmethyl)-8- INT-983 (3-cyanooxetan- step 1 of INT- 441.3 (dimethylamino)-2-oxo-8-phenyl- 3-yl)methyl 4- 897 (for step 1,3-diazaspiro[4.5]decan-3- methylbenzenesulfonate 1), SC_5034 yl)methyl)oxetane-3-carboxamide (step 1) (for step 2) SC_5087 CIS-3-(1-(cyclopropylmethyl)-8- SC_5073 step 2 of 413.3 (methylamino)-2-oxo-8-phenyl-1,3- SC_5063 diazaspiro[4.5]decan-3-yl)-2,2- dimethylpropanamide SC_5088 CIS-3-(1-(cyclopropylmethyl)-8- INT-983 3- step 1 of INT- (dimethylamino)-2-oxo-8-phenyl- bromopropanenitrile 897 (for step 1,3-diazaspiro[4.5]decan-3- 1), SC_5034 yl)propanamide (for step 2) SC_5089 CIS-3-(8-(dimethylamino)-1-((1- INT-976 3-bromo-2,2- step 1 of INT- fluorocyclopropyl)methyl)-2-oxo-8- dimethyl-propionitrile 897 (for step phenyl-1,3-diazaspiro[4.5]decan-3- (step 1), (1- 1), step 1 of yl)-2,2-dimethylpropanamide fluorocyclopropyl)methyl INT-953 (for 4-methylbenzenesulfonate step 2), (step 2), SC_5034 (for H2O2 nitrile step 3) hydrolysis (step 3) (*comparative examples)

The chemical structures of the example compounds are shown in the following table.

(*comparative examples)

Pharmacological Investigations

Functional investigation on the human mu-opioid receptor (hMOP), human kappa-opioid receptor (hKOP), human delta-opioid receptor (hDOP), and human nociceptin/orphanin FQ peptide receptor (hNOP)

Human Mu-Opioid Peptide (hMOP) Receptor Binding Assay

The hMOP receptor binding assay was performed as homogeneous SPA-assay (scintillation proximity assay) using the assay buffer 50 mM TRIS-HCl (pH 7.4) supplemented with 0.052 mg/ml bovine serum albumin (Sigma-Aldrich Co. St. Louis. Mo.). The final assay volume (250 μl/well) included 1 nM of [N-allyl-2.3-³H]naloxone as ligand (PerkinElmer Life Sciences, Inc. Boston. Mass. USA). and either test compound in dilution series or 25 μM unlabelled naloxone for determination of unspecific binding. The test compound was diluted with 25% DMSO in H₂O to yield a final 0.5% DMSO concentration. which also served as a respective vehicle control. The assay was started by adding wheat germ agglutinin coated SPA beads (GE Healthcare UK Ltd. Buckinghamshire. UK) which had been preloaded with hMOP receptor membranes (PerkinElmer Life Sciences. Inc. Boston, Mass. USA). After incubation for 90 minutes at RT and centrifugation for 20 minutes at 500 rpm the signal rate was measured by means of a 1450 Microbeta Trilux β-counter (PerkinElmer Life Sciences/Wallac. Turku. Finland). Half-maximal inhibitory concentration (IC50) values reflecting 50% displacement of [³H]naloxone-specific receptor binding were calculated by nonlinear regression analysis and Ki values were calculated by using the Cheng-Prusoff equation. (Cheng and Prusoff 1973).

Human Kappa-Opioid Peptide (hKOP) Receptor Binding Assay

The hKOP receptor binding assay is run as homogeneous SPA-assay (scintillation proximity assay) using the assay buffer 50 mM TRIS-HCl (pH 7.4) supplemented with 0.076 mg BSA/ml. The final assay volume of 250 μl per well includes 2 nM of [³H]U69,593 as ligand, and either test compound in dilution series or 100 μM unlabelled naloxone for determination of unspecific binding. The test compound is diluted with 25% DMSO in H₂O to yield a final 0.5% DMSO concentration which serves as respective vehicle control, as well. The assays are started by the addition of wheat germ agglutinin coated SPA beads (1 mg SPA beads/250 μl final assay volume per well) which has been preloaded for 15 minutes at room temperature with hKOP receptor membranes (14.8 μg/250 μl final assay volume per well). After short mixing on a mini-shaker, the microtiter plates are covered with a lid and the assay plates are incubated for 90 minuets at room temperature. After this incubation, the microtiter plates are sealed with a topseal and centrifuged for 20 minutes at 500 rpm. The signal rate is measured after a short delay of 5 minutes by means of a 1450 Microbeta Trilux β-counter (PerkinElmer Life Sciences/Wallac, Turku, Finland). Half-maximal inhibitory concentration (IC50) values reflecting 50% displacement of [³H]U69.593-specific receptor binding are calculated by nonlinear regression analysis and K_(i) values are calculated by using the Cheng-Prusoff equation, (Cheng and Prusoff, 1973).

Human Delta-Opioid Peptide (hDOP) Receptor Binding Assay

The hDOP receptor binding assay is performed as homogeneous SPA-assay using the assay buffer 50 mM TRIS-HCl, 5 mM MgCl₂ (pH 7.4). The final assay volume (250 μl/well) includes 1 nM of [Tyrosyl-3,5-³H]2-D-Ala-deltorphin II as ligand, and either test compound in dilution series or 10 μM unlabelled naloxone for determination of unspecific binding. The test compound is diluted with 25% DMSO in H₂O to yield a final 0.5% DMSO concentration which serves as respective vehicle control, as well. The assays are started by the addition of wheat germ agglutinin coated SPA beads (1 mg SPA beads/250 μl final assay volume per well) which has been preloaded for 15 minutes at room temperature with hDOP receptor membranes (15.2 μg/250 μl final assay volume per well). After short mixing on a mini-shaker, the microtiter plates are covered with a lid and the assay plates are incubated for 120 minutes at room temperature and centrifuged for 20 minutes at 500 rpm. The signal rate is measured by means of a 1450 Microbeta Trilux β-counter (PerkinElmer Life Sciences/Wallac, Turku, Finland). Half-maximal inhibitory concentration (IC50) values reflecting 50% displacement of [Tyrosyl-3,5-³H]2-D-Ala-deltorphin II-specific receptor binding are calculated by nonlinear regression analysis and K_(i) values are calculated by using the Cheng-Prusoff equation, (Cheng and Prusoff, 1973).

Human Nociceptin/Orphanin FQ Peptide (hNOP) Receptor Binding Assay

The hNOP receptor binding assay was performed as homogeneous SPA-assay (scintillation proximity assay) using the assay buffer 50 mM TRIS-HCl. 10 mM MgCl₂. 1 mM EDTA (pH 7.4). The final assay volume (250 μl/well) included 0.5 nM of [leucyl-³H]nociceptin as ligand (PerkinElmer Life Sciences. Inc. Boston. Mass. USA). and either test compound in dilution series or 1 μM unlabelled nociceptin for determination of unspecific binding. The test compound was diluted with 25% DMSO in H₂O to yield a final 0.5% DMSO concentration. which also served as a respective vehicle control. The assay was started by adding wheat germ agglutinin coated SPA beads (GE Healthcare UK Ltd. Buckinghamshire. UK) which had been preloaded with hMOP receptor membranes (PerkinElmer Life Sciences. Inc. Boston. Mass. USA). After incubation for 60 minutes at RT and centrifugation for 20 minutes at 500 rpm the signal rate was measured by means of a 1450 Microbeta Trilux β-counter (PerkinElmer Life Sciences/Wallac. Turku. Finland). Half-maximal inhibitory concentration (IC50) values reflecting 50% displacement of [³H]nociceptin-specific receptor binding were calculated by nonlinear regression analysis and Ki values were calculated by using the Cheng-Prusoff equation. (Cheng and Prusoff, 1973).

Example hNOP Ki [nM] hMOP Ki [nM] SC_5001 4 410 SC_5002 12.2 118 SC_5003 2.6 44.5 SC_5004 1.1 10 SC_5005 1.2 46.5 SC_5006 1.9 24.5 SC_5007 2.1 66 SC_5008 1 25 SC_5009 1.8 43.5 SC_5010 2.2 19 SC_5011 2.6 51.5 SC_5012 5.8 28 SC_5013 3.6 8.2 SC_5014 6.6 33 SC_5015 10.6 24.5 SC_5016 11.4 31 SC_5017 2.6 7.6 SC_5018 3.2 1.7 SC_5019 3 49 SC_5020 8.1 47.5 SC_5022 3.1 99.5 SC_5023 14.5 245 SC_5024 9.4 160 SC_5025 22.5 130 SC_5026 17.5 555 SC_5027 215 1195 SC_5028 140 895 SC_5029 205 1635 SC_5030 20 810 SC_5031 195 510 SC_5032 220 1130 SC_5033 48.5 1030 SC_5034 130 1185 SC_5035 230 815 SC_5036 4.2 140 SC_5037 8 40 SC_5038 72.5 175 SC_5039 130.5 130 SC_5040 115.5 395 SC_5041 63.5 445 SC_5042 70.5 190 SC_5043 101 210 SC_5044 5.6 160.5 SC_5045 19 910 SC_5046 1 113.4 SC_5047 5.8 69 SC_5048 1195 4146.7 SC_5049 1.5 11.3 SC_5051 3.6 320 SC_5052 12 250 SC_5053 16.5 58.5 SC_5054 18.5 160 SC_5055 11.5 74 SC_5056 7.4 64 SC_5057 75.5 124 SC_5058 19.5 545 SC_5059 111.5 88.5 SC_5060 285 1300 SC_5064 3%@1 μM (DOP 20%) 3%@1 μM SC_5066 0%@1 μM (DOP 22%) 7%@1 μM SC_5067 1300 11%@1 μM  SC_5069 1%@1 μM (KOP 50%) 7%@1 μM SC_5070 245 7340 SC_5071 625 2845 SC_5072 150 4675 SC_5073 23 480 SC_5074 260 2615 SC_5076 7 670 SC_5077 15 485 SC_5078 0.5 180 SC_5079 12 510 SC_5081 815 4025 SC_5082 340 790 SC_5083 22 610 SC_5084 12 2475

Protocol for [³⁵S]GTPγS Functional NOP/MOP/KOP/DOP Assays

Cell membrane preparations of CHO-K1 cells transfected with the human MOP receptor (Art.-No. RBHOMM) or the human DOP receptor (Art.-No.RBHODM), and HEK293 cells transfected with the human NOP receptor (Art.-No.RBHORLM) or the human KOP receptor (Art.-No. 6110558) are available from PerkinElmer (Waltham, Mass.). Membranes from CHO-K1 cells transfected with the human nociceptin/orphanin FQ peptide (hNOP) receptor (Art.-No. 93-0264C2, DiscoveRx Corporation Freemont, Calif.) are also used. [³⁵S]GTPγS (Art.-No. NEG030H; Lot-No. #0112, #0913, #1113 calibrated to 46.25 TBq/mmol) is available from PerkinElmer (Waltham, Mass.).

The [³⁵S]GTPγS assays are carried out essentially as described by Gillen et al (2000). They are run as homogeneous scintillation proximity (SPA) assays in microtiter luminescence plates, where each well contains 1.5 ng of WGA-coated SPA-beads. To test the agonistic activity of test compounds on recombinant hNOP, hMOP, hDOP, and hKOP receptor expressing cell membranes from CHO-K1 or HEK293 cells, 10 or 5 μg membrane protein per assay are incubated with 0.4 nM [³⁵S]GTPγS and serial concentrations of receptor-specific agonists in buffer containing 20 mM HEPES pH 7.4, 100 mM NaCl, 10 mM MgCl2, 1 mM EDTA, 1 mM dithiothreitol, 1.28 mM NaN₃, and 10 μM GDP for 45 min at room temperature. The microtiter plates are then centrifuged for 10 min at 830 to sediment the SPA beads. The microtiter plates are sealed and the bound radioactivity [cpm] is determined after a delay of 15 min by means of a 1450 Microbeta Trilux (PerkinElmer, Waltham, Mass.).

The unstimulated basal binding activity (UBS_(obs) [cpm]) is determined from 12 unstimulated incubates and is set as 100% basal binding. For determination of the potency and the efficacy, the arithmetic mean of the observed total [³⁵S]GTPγS binding (TB_(obs) [cpm]) of all incubates (duplicates) stimulated by the receptor-specific agonists (i.e. N/OFQ, SNC80, DAMGO, or U69,593) are transformed in percent total binding (TB_(obs) [%]) relative to the basal binding activity (i.e. 100% binding). The potency (EC₅₀) of the respective agonist and its maximal achievable total [³⁵S]GTPγS binding (TB_(calc) [%]) above its calculated basal binding (UBS_(calc) [%]) are determined from its transformed data (TB_(obs) [%]) by means of nonlinear regression analysis with XLfit for each individual concentration series. Then the difference between the calculated unstimulated [³⁵S]GTPγS binding (UBS_(calc) [%]) and the maximal achievable total [³⁵S]GTPγS binding (TB_(calc) [%]) by each tested agonist is determined (i.e. Bl_(calc) [%]). This difference (Bl_(calc) [%]) as a measure of the maximal achievable enhancement of [³⁵S]GTPγS binding by a given agonist is used to calculate the relative efficacy of test compounds versus the maximal achievable enhancement by a receptor-specific full agonist, e.g. N/OFQ (Bl_(calc-N/OFQ) [%]) which is set as 100% relative efficacy for the hNOP receptor. Likewise, the percentage efficacies of test compounds at the hDOP, hMOP, or hKOP receptor are determined versus the calculated maximal enhancement of [³⁵S]GTPγS binding by the full agonists SNC80 (Bl_(calc-SNC80) [%]), DAMGO (Bl_(calc-DAMGO) [%]) and U69,593 (Bl_(calc-U69,593) [%]) which are set as 100% relative efficacy at each receptor, respectively.

The foregoing description and examples have been set forth merely to illustrate the invention and are not intended to be limiting. Since modifications of the described embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed broadly to include all variations within the scope of the appended claims and equivalents thereof. 

1. A compound according to general formula (I)

wherein R¹ and R² independently of one another mean —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —OH, —OCH₃, —CN and —CO₂CH₃; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —OH, —OCH₃, —CN and —CO₂CH₃; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted; or a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —OH, —OCH₃, —CN and —CO₂CH₃; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted; or R¹ and R² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆—; —(CH₂)₂—O—(CH₂)₂—; or —(CH₂)₂—NR^(A)—(CH₂)₂—, wherein R^(A) means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br and —I; R³ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; R⁴ means —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said —C₁-C₆-alkyl is optionally connected through —C(═O)—, —C(═O)O—, or —S(═O)₂—; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 6-14-membered aryl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or wherein said 5-14-membered heteroaryl moiety is optionally connected through —C(═O)—, —C(═O)O—, —C(═O)O—CH₂—, or —S(═O)₂—; X means —O—, —S— or —NR⁶—; R⁵ means —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; in case X means NR⁶, R⁶ means —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or poly substituted; or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ independently of one another mean —H, —F, —Cl, —Br, —I, —OH, or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or R⁷ and R⁸ together with the carbon atom to which they are attached form a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; or a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein “mono- or polysubstituted” means that one or more hydrogen atoms are replaced by a substituent independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —R²¹, —C(═O)R²¹, —C(═O)OR²¹, —C(═O)NR²¹R²², —O—(CH₂CH₂—O)₁₋₃₀—H, —O—(CH₂CH₂—O)₁₋₃₀—CH₃, ═O, —OR²¹, —OC(═O)R²¹, —OC(═O)OR²¹, —OC(═O)NR²¹R²², —NO₂, —NR²¹R²², —NR²¹—(CH₂)₁₋₆—C(═O)R²², —NR²¹—(CH₂)₁₋₆—C(═O)OR²², —NR²³—(CH₂)₁₋₆—C(═O)NR²¹R²², —NR²¹C(═O)R²², —NR²¹C(═O)—OR²², —NR²³C(═O)NR²¹R²², —NR²¹S(═O)₂R²², —SR²¹, —S(═O)R²¹, —S(═O)₂R²¹, —S(═O)₂OR²¹, and —S(═O)₂NR²¹R²²; wherein R²¹, R²² and R²³ independently of one another mean —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, and —O—C₁-C₆-alkyl; a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted; wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, —NH₂, —C₁-C₆-alkyl and —O—C₁-C₆-alkyl; or R²¹ and R²² within —C(═O)NR²¹R²², —OC(═O)NR²¹R²², —NR²¹R²², —NR²³—(CH₂)₁₋₆—C(═O)NR²¹R²², —NR²³C(═O)NR²¹R²², or —S(═O)₂NR²¹R²² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆₋, —(CH₂)₂—O—(CH₂)₂—; or —(CH₂)₂—NR^(B)—(CH₂)₂—, wherein R^(B) means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br and —I; or a physiologically acceptable salt thereof.
 2. The compound according to claim 1, wherein R⁷ and R⁸ independently of one another mean —H or —C₁-C₆-alkyl.
 3. The compound according to claim 1, wherein R⁷ and R⁸ together with the carbon atom to which they are attached form a ring selected from the group consisting of cyclopropyl, cyclobutyl or cyclopentyl, oxetanly, tetrahydrofuranyl or tetrahydropyranyl, in each case unsubstituted.
 4. The compound according to claim 1, wherein R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ independently of one another mean —H, —F, —OH, or —C₁-C₆-alkyl.
 5. The compound according to claim 1, wherein R¹ means —H; and R² means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 6. The compound according to claim 1, wherein R¹ means —CH₃; and R² means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 7. The compound according to claim 1, wherein R¹ means —H or —CH₃; and wherein R² means —CH₂-cycloalkyl, —CH₂-cyclobutyl, —CH₂-cyclopentyl, —CH₂-oxetanyl or —CH₂-tetrahydrofuranyl.
 8. The compound according to claim 1, wherein R¹ and R² together with the nitrogen atom to which they are attached form a ring and mean —(CH₂)₃₋₆—.
 9. The compound according to claim 1, wherein R³ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 10. The compound according to claim 1, wherein R³ means a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted.
 11. The compound according to claim 1, wherein R³ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted.
 12. The compound according to claim 1, wherein R⁴ means —H.
 13. The compound according to claim 1, wherein R⁴ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 14. The compound according to claim 1, wherein R⁴ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein the 3-12-membered cycloalkyl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 15. The compound according to claim 1, wherein R⁴ means a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 16. The compound according to claim 1, wherein R⁴ means a 6-14-membered aryl moiety, unsubstituted, mono- or polysubstituted; wherein said 6-14-membered aryl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 17. The compound according to claim 1, wherein R⁴ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 18. The compound according to claim 1, wherein R⁵ means —H.
 19. The compound according to claim 1, wherein R⁵ means —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 20. The compound according to claim 1, wherein R⁵ means a 3-12-membered cycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted, wherein said 3-12-membered cycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 21. The compound according to claim 1, wherein R⁵ means a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted; wherein said 3-12-membered heterocycloalkyl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 22. The compound according to claim 1, wherein R⁵ means a 5-14-membered heteroaryl moiety, unsubstituted, mono- or polysubstituted; wherein said 5-14-membered heteroaryl moiety is optionally connected through —C₁-C₆-alkylene-, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 23. The compound according to claim 1, wherein X means NR⁶ and R⁵ and R⁶ together with the nitrogen atom to which they are attached form a 3-12-membered heterocycloalkyl moiety, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 24. The compound according to claim 1, wherein X means NR⁶ and R⁶ means —H or —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted, mono- or polysubstituted.
 25. The compound according to claim 1, which has a structure according to any of general formulas (II-A) to (VIII-C):

wherein in each case R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, and X are defined as in claim 1, R^(C) means —H, —OH, —F, —CN or —C₁-C₄-alkyl; R^(D) means —H or —F; or a physiologically acceptable salt thereof.
 26. The compound according to claim 1, wherein the substructure

has a meaning selected from the group consisting of:


27. The compound according to claim 1, wherein R¹ means —H or —CH₃; R² means —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted; R³ means -phenyl, -thienyl or -pyridinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —CN, —CH₃, —CH₂CH₃, —CF₃, —OCF3, —OH, —OCH₃, —C(═O)NH₂, C(═O)NHCH₃, —C(═O)N(CH₃)₂, —NH₂, —NHCH₃, —N(CH₃)₂, —NHC(═O)CH₃, —CH₂OH, —SOCH₃ and —SO₂CH₃; R⁴ means —H; —C₁-C₆-alkyl, linear or branched, saturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl; 3-6-membered cycloalkyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered cycloalkyl is connected through —C₁-C₆-alkylene; or 3-6-membered heterocycloalkyl, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —OH, and —O—C₁-C₄-alkyl, wherein said 3-6-membered heterocycloalkyl is connected through —C₁-C₆-alkylene; X means —O— or —NR⁶—; R⁵ means —H; —C₁-C₆-alkyl, linear or branched, saturated or unsaturated, unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, —Br, —I, —CN, —O—C₁-C₄-alkyl, —C(═O)OH, —C(═O)OC₁-C₄-alkyl, —C(═O)NH₂, —C(═O)NHC₁-C₄-alkyl, —C(═O)N(C₁-C₄-alkyl)₂, —OH, —S(═O)C₁-C₄-alkyl and —S(═O)₂ C₁-C₄-alkyl; -cyclobutyl, unsubstituted or monosubstituted with —OH; wherein said -cyclobutyl is connected through —CH₂—; -heterocyclobutyl, unsubstituted; or -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of —F, —Cl, Br, —I, —OH, —CN, and —S(═O)₂C₁-C₄-alkyl; wherein said -oxazolyl, -pyridinyl, -pyridazinyl or -pyrimidinyl is optionally connected through —CH₂—; in case X means NR⁶, R⁶ means —H or —CH₃; or in case X means NR⁶, R⁵ and R⁶ together with the nitrogen atom to which they are attached form a piperidine moiety, a pyrrolidine moiety, a morpholine moiety, a thiomorpholine moiety, a thiomorpholine dioxide moiety, or a piperazine moiety, in each case unsubstituted or substituted with one, two, three or four substituents independently of one another selected from the group consisting of ═O, —OH, and —C(═O)NH₂; wherein said piperidine moiety, pyrrolidine moiety, morpholine moiety, thiomorpholine moiety, thiomorpholine dioxide moiety, or piperazine moiety is optionally condensed with an imidazole moiety, unsubstituted; R⁷ and R⁸ independently of one another mean —H or —CH₃; or R⁷ and R⁸ together with the carbon atom to which they are attached form a ring selected from the group consisting of cyclopropyl, cyclobutyl, heterocyclobutyl and heterocyclohexyl, in each case unsubstituted; and R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, and R²⁰ mean —H.
 28. The compound according to claim 1, which has a structure according to general formula (I′)

wherein R¹ to R⁵, R⁷ to R²⁰, and X are defined as in claim 1, or a physiologically acceptable salt thereof.
 29. The compound according to claim 1, which has a structure according to general formula (IX)

wherein R^(C) means —H or —OH; R^(D) means —H or —F; R⁵ means —H, —CH₃, or —CH₂CH₂—OH; R⁶ means —H or —CH₃; and R⁷ means —CH₃ and R⁸ means —CH₃; or R⁷ and R⁸ together with the carbon atom to which they are attached form a cyclopropyl ring; or a physiologically acceptable salt thereof.
 30. The compound according to claim 1, which is selected from the group consisting of CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-pyridin-4-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyridin-3-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(3-methoxy-pyridin-4-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyridazin-3-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(5-methylsulfonyl-pyridin-2-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(5-methoxy-pyridin-2-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(6-methylsulfonyl-pyridin-3-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(6-methoxy-pyrazin-2-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(4-methoxy-pyridin-2-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxazol-5-yl-methyl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxazol-2-yl-methyl)-propionamide; CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-piperidin-1-yl]-3-oxo-propyl]-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-1-(Cyclobutyl-methyl)-3-[3-[3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo-propyl]-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-1-(Cyclobutyl-methyl)-3-[3-[(3S,4R)-3,4-dihydroxy-pyrrolidin-1-yl]-3-oxo-propyl]-8-dimethylamino-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3-[3-(3-hydroxy-piperidin-1-yl)-3-oxo-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-[(1-hydroxy-cyclobutyl)-methyl]-propionamide; CIS-1-(Cyclobutyl-methyl)-8-dimethylamino-3-[3-oxo-3-(5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyrazin-7-yl)-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-3-[3-[1-(Cyclobutyl-methyl)-8-dimethyl amino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propanoylamino]-N,N-dimethyl-propionamide; CIS-N-(2-Cyano-pyrimidin-5-yl)-3-[8-dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyrimidin-2-yl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(4-hydroxy-pyrimidin-2-yl)-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(4-methoxy-pyrimidin-2-yl)-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridazin-3-yl-propionamide; CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide; CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide; CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyrimidin-5-yl-propionamide; CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-Dimethylamino-1-(2-methoxy-ethyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-3-yl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-4-yl-propionamide; CIS-2-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propanoylamino]-2-methyl-propionamide; CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methylsulfonyl-ethyl)-propionamide; CIS-3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide; CIS-8-Dimethylamino-1-(3-methoxy-propyl)-3-[3-oxo-3-(3-oxo-piperazin-1-yl)-propyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-(2R)-1-[3-[8-Dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propanoyl]-pyrrolidine-2-carboxylic acid amide; CIS-N-(Carbamoyl-methyl)-3-[8-dimethylamino-1-(3-methoxy-propyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyridin-2-yl-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-(ethyl-methyl-amino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-[methyl-(2-methyl-propyl)-amino]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-pyrimidin-5-yl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-methyl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-methoxy-ethyl)-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide; CIS-N-(Carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-dimethyl-amino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-N-(Carbamoyl-methyl)-3-[1-(cyclobutyl-methyl)-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(oxetan-3-yl)-propionamide; CIS-3-[1-[(1-Hydroxy-cyclobutyl)-methyl]-8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-(Ethyl-methyl-amino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-(Ethyl-methyl-amino)-1-methyl-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-2,2-Dimethyl-3-(8-methylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-propionamide; CIS-3-(8-Ethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl-propionamide; CIS-3-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl-propionamide; CIS-3-[1-(Cyclobutyl-methyl)-8-ethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-Dimethylamino-1-(oxetan-3-yl-methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[1-(Cyclopropyl-methyl)-8-dimethyl amino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-3-[8-(Ethyl-methyl-amino)-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-8-Dimethylamino-3-(2,2-dimethyl-3-morpholin-4-yl-3-oxo-propyl)-1-[(1-hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; CIS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-N-(2-hydroxy-ethyl)-2,2-dimethyl-propionamide; CIS-3-[1-[(1-Cyano-cyclobutyl)-methyl]-8-dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-8-Dimethylamino-3-[3-(1,1-dioxo-[1,4]thiazinan-4-yl)-2,2-dimethyl-3-oxo-propyl]-1-[(1-hydroxy-cyclobutyl)-methyl]-8-phenyl-1,3-diazaspiro[4.5]decan-2-one; TRANS-3-[8-Dimethylamino-1-[(1-hydroxy-cyclobutyl)-methyl]-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide TRANS-3-(8-Dimethylamino-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethyl-propionamide; CIS-3-[1-(Cyclopropyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl]-N,N-dimethyl-propionamide; CIS-3-[1-(Cyclopropyl-methyl)-8-dimethylamino-8-(3-fluorophenyl)-2-oxo-1,3-diazaspiro[4.5]decan-3-yl]-2,2-dimethyl-propionamide; CIS-1-((1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)methyl)cyclopropanecarboxamide; CIS-3-((1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)methyl)oxetane-3-carboxamide; CIS-3-(1-(cyclopropylmethyl)-8-(methylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide; CIS-3-(1-(cyclopropylmethyl)-8-(dimethylamino)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)propanamide; CIS-3-(8-(dimethylamino)-1-((1-fluorocyclopropyl)methyl)-2-oxo-8-phenyl-1,3-diazaspiro[4.5]decan-3-yl)-2,2-dimethylpropanamide and the physiologically acceptable salts thereof.
 31. The compound according to claim 1 for use in the treatment of pain.
 32. A medicament comprising a compound according to claim
 1. 